Make app_custom_bindings.js lazily evaluated so it doesn't execute on every page load.

chrome/renderer/module_system.cc

Index: chrome/renderer/module_system.cc
diff --git a/chrome/renderer/module_system.cc b/chrome/renderer/module_system.cc
index 8d45dfe1f45c7c186b7b61ecfcce588e9265a698..151be28a524a242accf9562ffb373eeefbc8c37f 100644
--- a/chrome/renderer/module_system.cc
+++ b/chrome/renderer/module_system.cc
@@ -29,6 +29,16 @@ ModuleSystem::ModuleSystem(SourceMap* source_map)
 ModuleSystem::~ModuleSystem() {
 }
 
+ModuleSystem::NativesEnabledScope::NativesEnabledScope(
+    ModuleSystem* module_system)
+    : module_system_(module_system) {
+  module_system_->set_natives_enabled(true);

[not at google - send to devlin, 2012/03/25 22:42:58]

This won't work with nested "natives enabled" scopes. Making it work with nested
scoped would be a bit of a pain, you'd need to make natives enabled a counter
rather than a boolean or something.

I would say "fine to just CHECK that natives is disabled" and that would be
equivalent if GetterRouter below can't be called while natives is enabled, but
is that true? What if an extension references "chrome.app" in its startup
sequence?

[koz (OOO until 15th September), 2012/03/26 01:36:09]

Good point. I've made it a counter and removed the set_natives_enabled() method.

+}
+
+ModuleSystem::NativesEnabledScope::~NativesEnabledScope() {
+  module_system_->set_natives_enabled(false);
+}
+
 void ModuleSystem::Require(const std::string& module_name) {
   v8::HandleScope handle_scope;
   RequireForJsInner(v8::String::New(module_name.c_str()));
@@ -91,8 +101,12 @@ v8::Handle<v8::Value> ModuleSystem::GetterRouter(
   ModuleSystem* module_system = static_cast<ModuleSystem*>(
       v8::Handle<v8::External>::Cast(module_system_value)->Value());
 
-  v8::Handle<v8::Object> module = module_system->RequireForJsInner(
-      parameters->Get(v8::String::New(kModuleName))->ToString())->ToObject();
+  v8::Handle<v8::Object> module;
+  {
+    NativesEnabledScope scope(module_system);
+    module = module_system->RequireForJsInner(
+        parameters->Get(v8::String::New(kModuleName))->ToString())->ToObject();

[not at google - send to devlin, 2012/03/25 22:42:58]

(see comment above)

[koz (OOO until 15th September), 2012/03/26 01:36:09]

Done.

+  }
 
   v8::Handle<v8::String> field =
       parameters->Get(v8::String::New(kModuleField))->ToString();