Remove more calls to HandleScope default ctor.

chrome/renderer/extensions/chrome_v8_context.h

Index: chrome/renderer/extensions/chrome_v8_context.h
diff --git a/chrome/renderer/extensions/chrome_v8_context.h b/chrome/renderer/extensions/chrome_v8_context.h
index 930807b6dafac04a6d83ed12acb479444683c9b1..8007bb2433f58a30303fe24634bc223c7e75b105 100644
--- a/chrome/renderer/extensions/chrome_v8_context.h
+++ b/chrome/renderer/extensions/chrome_v8_context.h
@@ -116,6 +116,10 @@ class ChromeV8Context : public RequestSender::Source {
                                   const base::ListValue& response,
                                   const std::string& error) OVERRIDE;
 
+  v8::Isolate* isolate() const {
+    return isolate_;

[Jeffrey Yasskin, 2013/09/05 17:36:26]

I believe you can get this from v8_context()->GetIsolate(), so you wouldn't need
to store isolate_.

[marja, 2013/09/06 08:31:24]

v8_context_ is a ScopedPersistent, and we shouldn't [be able to] call any V8
functions (such as GetIsolate) on it. Currently we can, but it's a hack and I
should remove it asap. So the only way to call a V8 function for a
ScopedPersistent is to create a new local handle based on it, and call the
function on the local handle. But the local handle needs a HandleScope, and the
HandleScope needs an Isolate, and that's a circle. I'm breaking the circle here
by storing the isolate.

[Jeffrey Yasskin, 2013/09/06 16:10:14]

Oh, I see. Certainly a good answer for this CL. I wonder if there should be a
curated list of v8 functions you can call on Persistents, which would include
GetIsolate but not any type-specific functions. But that's a design question,
and not about the cleanup you're currently doing.

+  }
+
  private:
   // The v8 context the bindings are accessible to.
   ScopedPersistent<v8::Context> v8_context_;
@@ -137,6 +141,8 @@ class ChromeV8Context : public RequestSender::Source {
   // Contains safe copies of builtin objects like Function.prototype.
   SafeBuiltins safe_builtins_;
 
+  v8::Isolate* isolate_;
+
   DISALLOW_COPY_AND_ASSIGN(ChromeV8Context);
 };