Pepper: Access PepperMediaDeviceManager through a WeakPtr

Its lifetime is scoped to the RenderFrame, and it might go away before the
hosts that refer to it.

BUG=423030

Review URL: https://codereview.chromium.org/653243003

Cr-Commit-Position: refs/heads/master@{#299897}

content/renderer/pepper/pepper_device_enumeration_host_helper.cc

@@ -46,6 +46,7 @@ class PepperDeviceEnumerationHostHelper::ScopedRequest
     // EnumerateDevicesCallbackBody() to ensure that we always call |callback|
     // asynchronously.
     sync_call_ = true;
+    DCHECK(owner_->delegate_);
     request_id_ = owner_->delegate_->EnumerateDevices(
         owner_->device_type_,
         owner_->document_url_,
@@ -54,7 +55,7 @@ class PepperDeviceEnumerationHostHelper::ScopedRequest
   }
 
   ~ScopedRequest() {
-    if (requested_) {
+    if (requested_ && owner_->delegate_) {
       owner_->delegate_->StopEnumerateDevices(request_id_);
     }
   }
@@ -91,7 +92,7 @@ class PepperDeviceEnumerationHostHelper::ScopedRequest
 
 PepperDeviceEnumerationHostHelper::PepperDeviceEnumerationHostHelper(
     ppapi::host::ResourceHost* resource_host,
-    Delegate* delegate,
+    base::WeakPtr<Delegate> delegate,
     PP_DeviceType_Dev device_type,
     const GURL& document_url)
     : resource_host_(resource_host),

content/renderer/pepper/pepper_device_enumeration_host_helper.h

@@ -10,6 +10,7 @@
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "content/common/content_export.h"
 #include "ppapi/c/dev/ppb_device_ref_dev.h"
 #include "ppapi/host/host_message_context.h"
@@ -58,7 +59,7 @@ class CONTENT_EXPORT PepperDeviceEnumerationHostHelper {
 
   // |resource_host| and |delegate| must outlive this object.
   PepperDeviceEnumerationHostHelper(ppapi::host::ResourceHost* resource_host,
-                                    Delegate* delegate,
+                                    base::WeakPtr<Delegate> delegate,
                                     PP_DeviceType_Dev device_type,
                                     const GURL& document_url);
   ~PepperDeviceEnumerationHostHelper();
@@ -93,7 +94,7 @@ class CONTENT_EXPORT PepperDeviceEnumerationHostHelper {
 
   // Non-owning pointers.
   ppapi::host::ResourceHost* resource_host_;
-  Delegate* delegate_;
+  base::WeakPtr<Delegate> delegate_;
 
   PP_DeviceType_Dev device_type_;
   GURL document_url_;

content/renderer/pepper/pepper_device_enumeration_host_helper_unittest.cc

@@ -7,6 +7,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
+#include "base/memory/weak_ptr.h"
 #include "content/renderer/pepper/pepper_device_enumeration_host_helper.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/host/host_message_context.h"
@@ -24,7 +25,8 @@ namespace content {
 
 namespace {
 
-class TestDelegate : public PepperDeviceEnumerationHostHelper::Delegate {
+class TestDelegate : public PepperDeviceEnumerationHostHelper::Delegate,
+                     public base::SupportsWeakPtr<TestDelegate> {
  public:
   TestDelegate() : last_used_id_(0) {}
 
@@ -76,7 +78,7 @@ class PepperDeviceEnumerationHostHelperTest : public testing::Test {
       : ppapi_host_(&sink_, ppapi::PpapiPermissions()),
         resource_host_(&ppapi_host_, 12345, 67890),
         device_enumeration_(&resource_host_,
-                            &delegate_,
+                            delegate_.AsWeakPtr(),
                             PP_DEVICETYPE_DEV_AUDIOCAPTURE,
                             GURL("http://example.com")) {}
 

content/renderer/pepper/pepper_media_device_manager.cc

@@ -25,13 +25,14 @@ ppapi::DeviceRefData FromStreamDeviceInfo(const StreamDeviceInfo& info) {
 
 }  // namespace
 
-PepperMediaDeviceManager* PepperMediaDeviceManager::GetForRenderFrame(
+base::WeakPtr<PepperMediaDeviceManager>
+PepperMediaDeviceManager::GetForRenderFrame(
     RenderFrame* render_frame) {
   PepperMediaDeviceManager* handler =
       PepperMediaDeviceManager::Get(render_frame);
   if (!handler)
     handler = new PepperMediaDeviceManager(render_frame);
-  return handler;
+  return handler->AsWeakPtr();
 }
 
 PepperMediaDeviceManager::PepperMediaDeviceManager(RenderFrame* render_frame)

content/renderer/pepper/pepper_media_device_manager.h

@@ -23,7 +23,8 @@ class PepperMediaDeviceManager
       public RenderFrameObserverTracker<PepperMediaDeviceManager>,
       public base::SupportsWeakPtr<PepperMediaDeviceManager> {
  public:
-  static PepperMediaDeviceManager* GetForRenderFrame(RenderFrame* render_frame);
+  static base::WeakPtr<PepperMediaDeviceManager> GetForRenderFrame(
+      RenderFrame* render_frame);
   virtual ~PepperMediaDeviceManager();
 
   // PepperDeviceEnumerationHostHelper::Delegate implementation:

content/renderer/pepper/pepper_platform_audio_input.cc

@@ -289,7 +289,7 @@ PepperMediaDeviceManager* PepperPlatformAudioInput::GetMediaDeviceManager() {
   RenderFrameImpl* const render_frame =
       RenderFrameImpl::FromRoutingID(render_frame_id_);
   return render_frame ?
-      PepperMediaDeviceManager::GetForRenderFrame(render_frame) : NULL;
+      PepperMediaDeviceManager::GetForRenderFrame(render_frame).get() : NULL;
 }
 
 }  // namespace content

content/renderer/pepper/pepper_platform_video_capture.cc

@@ -152,7 +152,7 @@ PepperMediaDeviceManager* PepperPlatformVideoCapture::GetMediaDeviceManager() {
   RenderFrameImpl* const render_frame =
       RenderFrameImpl::FromRoutingID(render_frame_id_);
   return render_frame ?
-      PepperMediaDeviceManager::GetForRenderFrame(render_frame) : NULL;
+      PepperMediaDeviceManager::GetForRenderFrame(render_frame).get() : NULL;
 }
 
 }  // namespace content