[tint][ir] Don't use capitalized diagnostic messages

As per docs/tint/diagnostics_guide.md

Change-Id: Id1d1c3bae98ecf3e15081abb3d59da4c46f296b4
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/186640
Reviewed-by: James Price <jrprice@google.com>
diff --git a/src/tint/lang/core/ir/validator.cc b/src/tint/lang/core/ir/validator.cc
index 9ffcc2e..31d0cb8 100644
--- a/src/tint/lang/core/ir/validator.cc
+++ b/src/tint/lang/core/ir/validator.cc
@@ -397,7 +397,7 @@
     auto& diag = AddError(src) << inst->FriendlyName() << ": ";
 
     if (current_block_) {
-        AddNote(current_block_) << "In block";
+        AddNote(current_block_) << "in block";
     }
     return diag;
 }
@@ -408,7 +408,7 @@
     auto& diag = AddError(src) << inst->FriendlyName() << ": ";
 
     if (current_block_) {
-        AddNote(current_block_) << "In block";
+        AddNote(current_block_) << "in block";
     }
 
     return diag;
@@ -420,7 +420,7 @@
     auto& diag = AddError(src) << inst->FriendlyName() << ": ";
 
     if (current_block_) {
-        AddNote(current_block_) << "In block";
+        AddNote(current_block_) << "in block";
     }
     return diag;
 }
@@ -574,7 +574,7 @@
     for (auto* inst : *blk) {
         if (inst->Block() != blk) {
             AddError(inst) << "block instruction does not have same block as parent";
-            AddNote(current_block_) << "In block";
+            AddNote(current_block_) << "in block";
             continue;
         }
         if (inst->Is<ir::Terminator>() && inst != blk->Terminator()) {
diff --git a/src/tint/lang/core/ir/validator_test.cc b/src/tint/lang/core/ir/validator_test.cc
index 762fe7d..9c321a7 100644
--- a/src/tint/lang/core/ir/validator_test.cc
+++ b/src/tint/lang/core/ir/validator_test.cc
@@ -71,7 +71,7 @@
   loop [b: $B2] {  # loop_1
   ^^^^^^^^^^^^^
 
-:1:1 note: In block
+:1:1 note: in block
 $B1: {  # root
 ^^^
 
@@ -102,7 +102,7 @@
   %1:ptr<private, i32, read_write> = var
                                      ^^^
 
-:1:1 note: In block
+:1:1 note: in block
 $B1: {  # root
 ^^^
 
@@ -257,7 +257,7 @@
     %2:void = call %g
                    ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -288,7 +288,7 @@
     %2:void = call %g
                    ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -325,7 +325,7 @@
     %5:void = call %g, 42i
                    ^^
 
-:7:3 note: In block
+:7:3 note: in block
   $B2: {
   ^^^
 
@@ -362,7 +362,7 @@
     %5:void = call %g, 1i, 2i, 3i
                    ^^
 
-:7:3 note: In block
+:7:3 note: in block
   $B2: {
   ^^^
 
@@ -399,7 +399,7 @@
     %6:void = call %g, 1i, 2.0f, 3i
                            ^^^^
 
-:7:3 note: In block
+:7:3 note: in block
   $B2: {
   ^^^
 
@@ -455,11 +455,11 @@
     %2:ptr<function, i32, read_write> = var
                                         ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -604,7 +604,7 @@
     %3:f32 = access %2, -1i
                         ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -635,7 +635,7 @@
     %3:f32 = access %2, 1u, 3u
                             ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -671,7 +671,7 @@
     %3:ptr<private, f32, read_write> = access %2, 1u, 3u
                                                       ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -705,7 +705,7 @@
     %3:f32 = access %2, 1u
                         ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -736,7 +736,7 @@
     %3:ptr<private, f32, read_write> = access %2, 1u
                                                   ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -773,7 +773,7 @@
     %4:i32 = access %2, %3
                         ^^
 
-:7:3 note: In block
+:7:3 note: in block
   $B1: {
   ^^^
 
@@ -816,7 +816,7 @@
     %4:i32 = access %2, %3
                         ^^
 
-:7:3 note: In block
+:7:3 note: in block
   $B1: {
   ^^^
 
@@ -852,7 +852,7 @@
     %3:i32 = access %2, 1u, 1u
              ^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -884,7 +884,7 @@
     %3:ptr<private, i32, read_write> = access %2, 1u, 1u
                                        ^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -916,7 +916,7 @@
     %3:f32 = access %2, 1u, 1u
              ^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -947,7 +947,7 @@
     %3:f32 = access %2, 1u
                         ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -992,7 +992,7 @@
     %3:f32 = access %2, 1u, 1u
                             ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1038,7 +1038,7 @@
     %3:ptr<uniform, f32, read> = access %2, 1u
                                  ^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1070,7 +1070,7 @@
     %3:ptr<storage, f32, read_write> = access %2, 1u
                                        ^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1127,7 +1127,7 @@
     ret
     ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1201,7 +1201,7 @@
     if 1i [t: $B2, f: $B3] {  # if_1
        ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1238,7 +1238,7 @@
     if undef [t: $B2, f: $B3] {  # if_1
        ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1277,7 +1277,7 @@
     undef = if true [t: $B2, f: $B3] {  # if_1
     ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1348,7 +1348,7 @@
   undef = var
   ^^^^^
 
-:1:1 note: In block
+:1:1 note: in block
 $B1: {  # root
 ^^^
 
@@ -1375,7 +1375,7 @@
     undef = var
     ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1405,7 +1405,7 @@
     %2:ptr<function, f32, read_write> = var, %3
                                         ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1434,7 +1434,7 @@
     undef = let 1i
     ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1463,7 +1463,7 @@
     %2:f32 = let undef
                  ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1493,7 +1493,7 @@
     %2:f32 = let 1i
              ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1524,7 +1524,7 @@
     <destroyed tint::core::ir::Var $ADDRESS>
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^$ARROWS^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1561,7 +1561,7 @@
     %2:ptr<function, f32, read_write> = var
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1592,7 +1592,7 @@
     %2:ptr<function, f32, read_write> = var, %3
                                              ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1623,7 +1623,7 @@
     %2:ptr<function, f32, read_write> = var, %3
                                              ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1673,7 +1673,7 @@
     %2:i32 = add undef, 2i
                  ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1700,7 +1700,7 @@
     %2:i32 = add 2i, undef
                      ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1730,7 +1730,7 @@
     undef = add 3i, 2i
     ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1757,7 +1757,7 @@
     %2:i32 = negation undef
                       ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1787,7 +1787,7 @@
     undef = negation 2i
     ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1818,7 +1818,7 @@
     %2:f32 = complement 2i
     ^^^^^^^^^^^^^^^^^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -1859,7 +1859,7 @@
         exit_if  # undef
         ^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # true
       ^^^
 
@@ -1898,7 +1898,7 @@
         exit_if 1i  # if_1
         ^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # true
       ^^^
 
@@ -1942,7 +1942,7 @@
         exit_if 1i, 2.0f, 3i  # if_1
         ^^^^^^^^^^^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # true
       ^^^
 
@@ -2003,7 +2003,7 @@
         exit_if 1i, 2i  # if_1
                     ^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # true
       ^^^
 
@@ -2043,7 +2043,7 @@
     exit_if  # if_1
     ^^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -2086,7 +2086,7 @@
             exit_if  # if_1
             ^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B3: {  # true
           ^^^
 
@@ -2139,7 +2139,7 @@
             exit_if  # if_1
             ^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B3: {  # case
           ^^^
 
@@ -2191,7 +2191,7 @@
             exit_if  # if_1
             ^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B3: {  # body
           ^^^
 
@@ -2250,7 +2250,7 @@
         exit_switch  # undef
         ^^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # case
       ^^^
 
@@ -2291,7 +2291,7 @@
         exit_switch 1i  # switch_1
         ^^^^^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # case
       ^^^
 
@@ -2335,7 +2335,7 @@
         exit_switch 1i, 2.0f, 3i  # switch_1
         ^^^^^^^^^^^^^^^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # case
       ^^^
 
@@ -2397,7 +2397,7 @@
         exit_switch 1i, 2i  # switch_1
                         ^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # case
       ^^^
 
@@ -2441,7 +2441,7 @@
         exit_switch  # switch_1
         ^^^^^^^^^^^
 
-:9:7 note: In block
+:9:7 note: in block
       $B3: {  # true
       ^^^
 
@@ -2522,7 +2522,7 @@
             exit_switch  # switch_1
             ^^^^^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B3: {  # case
           ^^^
 
@@ -2573,7 +2573,7 @@
             exit_switch  # switch_1
             ^^^^^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B3: {  # body
           ^^^
 
@@ -2630,7 +2630,7 @@
         exit_loop  # undef
         ^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # body
       ^^^
 
@@ -2673,7 +2673,7 @@
         exit_loop 1i  # loop_1
         ^^^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # body
       ^^^
 
@@ -2720,7 +2720,7 @@
         exit_loop 1i, 2.0f, 3i  # loop_1
         ^^^^^^^^^^^^^^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # body
       ^^^
 
@@ -2785,7 +2785,7 @@
         exit_loop 1i, 2i  # loop_1
                       ^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # body
       ^^^
 
@@ -2831,7 +2831,7 @@
         exit_loop  # loop_1
         ^^^^^^^^^
 
-:12:7 note: In block
+:12:7 note: in block
       $B4: {  # true
       ^^^
 
@@ -2914,7 +2914,7 @@
             exit_loop  # loop_1
             ^^^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B4: {  # case
           ^^^
 
@@ -2969,7 +2969,7 @@
             exit_loop  # loop_1
             ^^^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B4: {  # body
           ^^^
 
@@ -3019,7 +3019,7 @@
         exit_loop  # loop_1
         ^^^^^^^^^
 
-:7:7 note: In block
+:7:7 note: in block
       $B3: {  # continuing
       ^^^
 
@@ -3065,7 +3065,7 @@
             exit_loop  # loop_1
             ^^^^^^^^^
 
-:9:11 note: In block
+:9:11 note: in block
           $B4: {  # true
           ^^^
 
@@ -3117,7 +3117,7 @@
         exit_loop  # loop_1
         ^^^^^^^^^
 
-:4:7 note: In block
+:4:7 note: in block
       $B2: {  # initializer
       ^^^
 
@@ -3167,7 +3167,7 @@
             exit_loop  # loop_1
             ^^^^^^^^^
 
-:6:11 note: In block
+:6:11 note: in block
           $B5: {  # true
           ^^^
 
@@ -3230,7 +3230,7 @@
     ret
     ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3255,7 +3255,7 @@
     ret 42i
     ^^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3280,7 +3280,7 @@
     ret
     ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3306,7 +3306,7 @@
     ret 42.0f
     ^^^^^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3334,7 +3334,7 @@
     %2:i32 = load undef
                   ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3365,7 +3365,7 @@
     %3:f32 = load %l
                   ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3397,7 +3397,7 @@
     %3:f32 = load %2
                   ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3426,7 +3426,7 @@
     store undef, 42i
           ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3455,7 +3455,7 @@
     store %2, undef
               ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3486,7 +3486,7 @@
     store %l, 42u
               ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3517,7 +3517,7 @@
     store %2, 42u
               ^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3549,7 +3549,7 @@
     undef = load_vector_element %2, 1i
     ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3579,7 +3579,7 @@
     %2:f32 = load_vector_element undef, 1i
                                  ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3609,7 +3609,7 @@
     %3:f32 = load_vector_element %2, undef
                                      ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3639,7 +3639,7 @@
     store_vector_element undef, 1i, 2i
                          ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3669,7 +3669,7 @@
     store_vector_element %2, undef, 2i
                              ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3677,7 +3677,7 @@
     store_vector_element %2, undef, 2i
                                     ^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^
 
@@ -3708,7 +3708,7 @@
     store_vector_element %2, 1i, undef
                                  ^^^^^
 
-:2:3 note: In block
+:2:3 note: in block
   $B1: {
   ^^^