Split out the extensions gin::Runner implementation into a separate class.

extensions/renderer/script_context.h

Index: extensions/renderer/script_context.h
diff --git a/extensions/renderer/script_context.h b/extensions/renderer/script_context.h
index 862c0b510d2bde9b26e9c0c7b1cfbb82f3e8a0eb..5fd87df9b807c3717829ff089f762cb21349e70d 100644
--- a/extensions/renderer/script_context.h
+++ b/extensions/renderer/script_context.h
@@ -32,7 +32,7 @@ namespace extensions {
 class Extension;
 
 // Extensions wrapper for a v8 context.
-class ScriptContext : public RequestSender::Source, public gin::Runner {
+class ScriptContext : public RequestSender::Source {
  public:
   ScriptContext(const v8::Handle<v8::Context>& context,
                 blink::WebFrame* frame,
@@ -142,15 +142,6 @@ class ScriptContext : public RequestSender::Source, public gin::Runner {
                           const base::ListValue& response,
                           const std::string& error) override;
 
-  // gin::Runner overrides.
-  void Run(const std::string& source,
-           const std::string& resource_name) override;
-  v8::Handle<v8::Value> Call(v8::Handle<v8::Function> function,
-                             v8::Handle<v8::Value> receiver,
-                             int argc,
-                             v8::Handle<v8::Value> argv[]) override;
-  gin::ContextHolder* GetContextHolder() override;
-
   // Grants a set of content capabilities to this context.
   void SetContentCapabilities(const APIPermissionSet& permissions);
 
@@ -165,6 +156,8 @@ class ScriptContext : public RequestSender::Source, public gin::Runner {
   ScopedPersistent<v8::Context> v8_context_;
 
  private:
+  class Runner;
+
   // The WebFrame associated with this context. This can be NULL because this
   // object can outlive is destroyed asynchronously.
   blink::WebFrame* web_frame_;
@@ -197,6 +190,8 @@ class ScriptContext : public RequestSender::Source, public gin::Runner {
 
   GURL url_;
 
+  scoped_ptr<Runner> runner_;
+
   DISALLOW_COPY_AND_ASSIGN(ScriptContext);
 };