Allow nested compile-script histogram scopes.

src/compiler.cc

Index: src/compiler.cc
diff --git a/src/compiler.cc b/src/compiler.cc
index 544b4dd4595d0a07ec6a23a30bdc062882c5c4bc..5f99cb69ad602426b542036cc39bd35fe0c6d536 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -1263,7 +1263,7 @@ Handle<SharedFunctionInfo> Compiler::CompileScript(
     v8::Extension* extension, ScriptData** cached_data,
     ScriptCompiler::CompileOptions compile_options, NativesFlag natives) {
   Isolate* isolate = source->GetIsolate();
-  HistogramTimerScope total(isolate->counters()->compile_script());
+  HistogramTimerScope total(isolate->counters()->compile_script(), true);
 
   if (compile_options == ScriptCompiler::kNoCompileOptions) {
     cached_data = NULL;