translator: Scope all classes with "sh".

I was seeing an odd problem with our PoolAlloc conflicting with the
glslang/Vulkan TIntermNode, so the fix was to move everything to a
separate namespace.

The bison grammars are also regenerated. No functional changes.

BUG=angleproject:1576

Change-Id: I959c7afe4c092f0d458432c07b4dcee4d39513f3
Reviewed-on: https://chromium-review.googlesource.com/408267
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/compiler/translator/SeparateDeclarations.h b/src/compiler/translator/SeparateDeclarations.h
index 77913ab..2c2611a 100644
--- a/src/compiler/translator/SeparateDeclarations.h
+++ b/src/compiler/translator/SeparateDeclarations.h
@@ -16,8 +16,11 @@
 #ifndef COMPILER_TRANSLATOR_SEPARATEDECLARATIONS_H_
 #define COMPILER_TRANSLATOR_SEPARATEDECLARATIONS_H_
 
+namespace sh
+{
 class TIntermNode;
 
 void SeparateDeclarations(TIntermNode *root);
+}  // namespace sh
 
 #endif  // COMPILER_TRANSLATOR_SEPARATEDECLARATIONS_H_