Introduce gin_shell

gin/runner.h

Index: gin/runner.h
diff --git a/gin/runner.h b/gin/runner.h
index 3e999e1fe7558637548999e164400878da2c72d7..fa412598baee710a168ace9a067cbce0ec42333d 100644
--- a/gin/runner.h
+++ b/gin/runner.h
@@ -6,11 +6,14 @@
 #define GIN_RUNNER_H_
 
 #include <string>
+
+#include "base/memory/weak_ptr.h"
 #include "gin/context_holder.h"
 
 namespace gin {
 
 class Runner;
+class TryCatch;
 
 class RunnerDelegate {
  public:
@@ -19,8 +22,10 @@ class RunnerDelegate {
 
   // Returns the template for the global object.
   virtual v8::Handle<v8::ObjectTemplate> GetGlobalTemplate(Runner* runner);
-
   virtual void DidCreateContext(Runner* runner);
+  virtual void WillRunScript(Runner* runner, v8::Handle<v8::Script> script);
+  virtual void DidRunScript(Runner* runner, v8::Handle<v8::Script> script);
+  virtual void UnhandledException(Runner* runner, TryCatch& try_catch);
 };
 
 class Runner : public ContextHolder {
@@ -35,6 +40,10 @@ class Runner : public ContextHolder {
     return context()->Global();
   }
 
+  base::WeakPtr<Runner> GetWeakPtr() {
+    return weak_factory_.GetWeakPtr();
+  }
+
   class Scope {
    public:
     explicit Scope(Runner* runner);
@@ -52,6 +61,8 @@ class Runner : public ContextHolder {
 
   RunnerDelegate* delegate_;
 
+  base::WeakPtrFactory<Runner> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(Runner);
 };