[shuffle] Move builtin to new structure.

This CL moves the builtin folder into the `lang/base/builtin` folder and
updates the includes. The namespaces and build groups are not updated in
this CL, just the code move.

Bug: tint:1988
Change-Id: I8f0d583d0b0212ceec36a7537fd7452208891555
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/142163
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
diff --git a/src/tint/constant/composite.h b/src/tint/constant/composite.h
index 557ed7e..acaee30 100644
--- a/src/tint/constant/composite.h
+++ b/src/tint/constant/composite.h
@@ -15,11 +15,11 @@
 #ifndef SRC_TINT_CONSTANT_COMPOSITE_H_
 #define SRC_TINT_CONSTANT_COMPOSITE_H_
 
-#include "src/tint/builtin/number.h"
 #include "src/tint/constant/value.h"
 #include "src/tint/core/castable.h"
 #include "src/tint/core/hash.h"
 #include "src/tint/core/vector.h"
+#include "src/tint/lang/base/builtin/number.h"
 #include "src/tint/type/type.h"
 
 namespace tint::constant {
diff --git a/src/tint/constant/manager.h b/src/tint/constant/manager.h
index b91897d..5ff7076 100644
--- a/src/tint/constant/manager.h
+++ b/src/tint/constant/manager.h
@@ -17,10 +17,10 @@
 
 #include <utility>
 
-#include "src/tint/builtin/number.h"
 #include "src/tint/constant/value.h"
 #include "src/tint/core/hash.h"
 #include "src/tint/core/unique_allocator.h"
+#include "src/tint/lang/base/builtin/number.h"
 #include "src/tint/type/manager.h"
 
 namespace tint::constant {
diff --git a/src/tint/constant/scalar.h b/src/tint/constant/scalar.h
index 5218762..6b999e2 100644
--- a/src/tint/constant/scalar.h
+++ b/src/tint/constant/scalar.h
@@ -15,11 +15,11 @@
 #ifndef SRC_TINT_CONSTANT_SCALAR_H_
 #define SRC_TINT_CONSTANT_SCALAR_H_
 
-#include "src/tint/builtin/number.h"
 #include "src/tint/constant/manager.h"
 #include "src/tint/constant/value.h"
 #include "src/tint/core/castable.h"
 #include "src/tint/core/hash.h"
+#include "src/tint/lang/base/builtin/number.h"
 #include "src/tint/type/type.h"
 
 namespace tint::constant {
diff --git a/src/tint/constant/value.h b/src/tint/constant/value.h
index 8bb3b50..0e469c3 100644
--- a/src/tint/constant/value.h
+++ b/src/tint/constant/value.h
@@ -17,10 +17,10 @@
 
 #include <variant>
 
-#include "src/tint/builtin/number.h"
 #include "src/tint/constant/clone_context.h"
 #include "src/tint/constant/node.h"
 #include "src/tint/core/castable.h"
+#include "src/tint/lang/base/builtin/number.h"
 #include "src/tint/type/type.h"
 
 namespace tint::constant {