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/IntermTraverse.cpp b/src/compiler/translator/IntermTraverse.cpp
index c6a199e..7f91595 100644
--- a/src/compiler/translator/IntermTraverse.cpp
+++ b/src/compiler/translator/IntermTraverse.cpp
@@ -8,6 +8,9 @@
 #include "compiler/translator/InfoSink.h"
 #include "compiler/translator/SymbolTable.h"
 
+namespace sh
+{
+
 void TIntermSymbol::traverse(TIntermTraverser *it)
 {
     it->traverseSymbol(this);
@@ -831,3 +834,5 @@
 {
     visitRaw(node);
 }
+
+}  // namespace sh