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/ParseContext.cpp b/src/compiler/translator/ParseContext.cpp
index eb96d2a..4ca1e53 100644
--- a/src/compiler/translator/ParseContext.cpp
+++ b/src/compiler/translator/ParseContext.cpp
@@ -16,6 +16,9 @@
 #include "compiler/translator/ValidateGlobalInitializer.h"
 #include "compiler/translator/util.h"
 
+namespace sh
+{
+
 ///////////////////////////////////////////////////////////////////////
 //
 // Sub- vector and matrix fields
@@ -4454,3 +4457,5 @@
 
     return (error == 0) && (context->numErrors() == 0) ? 0 : 1;
 }
+
+}  // namespace sh