Renamed "symbols" to "internalized strings" throughout the code base,

src/string-stream.cc

Index: src/string-stream.cc
diff --git a/src/string-stream.cc b/src/string-stream.cc
index fc07d94ded237ee4ca79ebde48fe036680de6910..6d0563068695e29dbb99ae403f9c87a4fe3623c5 100644
--- a/src/string-stream.cc
+++ b/src/string-stream.cc
@@ -493,7 +493,7 @@ void StringStream::PrintFunction(Object* f, Object* receiver, Code** code) {
       // Common case: on-stack function present and resolved.
       PrintPrototype(fun, receiver);
       *code = fun->code();
-    } else if (f->IsSymbol()) {
+    } else if (f->IsInternalizedString()) {
       // Unresolved and megamorphic calls: Instead of the function
       // we have the function name on the stack.
       PrintName(f);