Cleanup some grammar.

This CL updates some grammar in break-if error messages.

Change-Id: I15ab6b98fd1b12dd4e6db16a28f0e311e9fee453
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/111102
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
diff --git a/src/tint/resolver/validation_test.cc b/src/tint/resolver/validation_test.cc
index c3893af..85b6967 100644
--- a/src/tint/resolver/validation_test.cc
+++ b/src/tint/resolver/validation_test.cc
@@ -849,7 +849,8 @@
     WrapInFunction(loop_stmt);
 
     EXPECT_FALSE(r()->Resolve());
-    EXPECT_EQ(r()->error(), R"(12:23 error: break-if must be last statement in a continuing block
+    EXPECT_EQ(r()->error(),
+              R"(12:23 error: break-if must be the last statement in a continuing block
 10:9 note: see continuing block here)");
 }
 
@@ -867,7 +868,8 @@
     WrapInFunction(loop_stmt);
 
     EXPECT_FALSE(r()->Resolve());
-    EXPECT_EQ(r()->error(), R"(12:23 error: break-if must be last statement in a continuing block
+    EXPECT_EQ(r()->error(),
+              R"(12:23 error: break-if must be the last statement in a continuing block
 10:9 note: see continuing block here)");
 }
 
diff --git a/src/tint/resolver/validator.cc b/src/tint/resolver/validator.cc
index df720a1..0b20c9b 100644
--- a/src/tint/resolver/validator.cc
+++ b/src/tint/resolver/validator.cc
@@ -1592,7 +1592,7 @@
         }
         if (auto* continuing = s->As<sem::LoopContinuingBlockStatement>()) {
             if (continuing->Declaration()->statements.Back() != stmt->Declaration()) {
-                AddError("break-if must be last statement in a continuing block",
+                AddError("break-if must be the last statement in a continuing block",
                          stmt->Declaration()->source);
                 AddNote("see continuing block here", s->Declaration()->source);
                 return false;
@@ -1601,7 +1601,7 @@
         }
     }
 
-    AddError("break-if must in a continuing block", stmt->Declaration()->source);
+    AddError("break-if must be in a continuing block", stmt->Declaration()->source);
     return false;
 }