Merge 112576 - [Chromium] WorkerFileSystemContextObserver can reference a deleted WorkerFileSystemC…

Source/WebKit/chromium/src/WorkerFileSystemCallbacksBridge.cpp

Index: Source/WebKit/chromium/src/WorkerFileSystemCallbacksBridge.cpp
===================================================================
--- Source/WebKit/chromium/src/WorkerFileSystemCallbacksBridge.cpp	(revision 112637)
+++ Source/WebKit/chromium/src/WorkerFileSystemCallbacksBridge.cpp	(working copy)
@@ -146,7 +146,7 @@
 // that it only gets deleted on the worker context thread which is verified by ~Observer.
 class WorkerFileSystemContextObserver : public WebCore::WorkerContext::Observer {
 public:
-    static PassOwnPtr<WorkerFileSystemContextObserver> create(WorkerContext* context, WorkerFileSystemCallbacksBridge* bridge)
+    static PassOwnPtr<WorkerFileSystemContextObserver> create(WorkerContext* context, PassRefPtr<WorkerFileSystemCallbacksBridge> bridge)
     {
         return adoptPtr(new WorkerFileSystemContextObserver(context, bridge));
     }
@@ -158,15 +158,13 @@
     }
 
 private:
-    WorkerFileSystemContextObserver(WorkerContext* context, WorkerFileSystemCallbacksBridge* bridge)
+    WorkerFileSystemContextObserver(WorkerContext* context, PassRefPtr<WorkerFileSystemCallbacksBridge> bridge)
         : WebCore::WorkerContext::Observer(context)
         , m_bridge(bridge)
     {
     }
 
-    // Since WorkerFileSystemCallbacksBridge manages the lifetime of this class,
-    // m_bridge will be valid throughout its lifetime.
-    WorkerFileSystemCallbacksBridge* m_bridge;
+    RefPtr<WorkerFileSystemCallbacksBridge> m_bridge;
 };
 
 void WorkerFileSystemCallbacksBridge::stop()