Cleanup of the metro viewer code

The main thing is the discovery of a clean way to retrieve the
corewindow hwnd based on ICoreWindowInterop, that removes some iffy
heuristic based on window name before.

From that we realize that we don't need some globals, namely the window
handle the thread id that owns the window.

BUG=151718
TEST=ash still works.
Review URL: https://codereview.chromium.org/13849005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193120 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 29 insertions, 24 deletions

diff --git a/win8/metro_driver/chrome_app_view_ash.cc b/win8/metro_driver/chrome_app_view_ash.cc
index ec59ba1..6d536fa 100644
--- a/win8/metro_driver/chrome_app_view_ash.cc
+++ b/win8/metro_driver/chrome_app_view_ash.cc
@@ -5,6 +5,7 @@
 #include "win8/metro_driver/stdafx.h"
 #include "win8/metro_driver/chrome_app_view_ash.h"
 
+#include <corewindow.h>
 #include <windows.foundation.h>
 
 #include "base/bind.h"
@@ -54,9 +55,6 @@ typedef int (__cdecl *BreakpadExceptionHandler)(EXCEPTION_POINTERS* info);
 
 // Global information used across the metro driver.
 struct Globals {
-  LPTHREAD_START_ROUTINE host_main;
-  HWND core_window;
-  DWORD main_thread_id;
   winapp::Activation::ApplicationExecutionState previous_state;
   winapp::Core::ICoreApplicationExit* app_exit;
   BreakpadExceptionHandler breakpad_exception_handler;
@@ -67,7 +65,6 @@ namespace {
 // TODO(robertshield): Share this with chrome_app_view.cc
 void MetroExit() {
   globals.app_exit->Exit();
-  globals.core_window = NULL;
 }
 
 class ChromeChannelListener : public IPC::Listener {
@@ -272,7 +269,9 @@ uint32 GetKeyboardEventFlags() {
 }  // namespace
 
 ChromeAppViewAsh::ChromeAppViewAsh()
-    : mouse_down_flags_(ui::EF_NONE), ui_channel_(nullptr) {
+    : mouse_down_flags_(ui::EF_NONE),
+      ui_channel_(nullptr),
+      core_window_hwnd_(NULL) {
   globals.previous_state =
       winapp::Activation::ApplicationExecutionState_NotRunning;
 }
@@ -285,8 +284,6 @@ IFACEMETHODIMP
 ChromeAppViewAsh::Initialize(winapp::Core::ICoreApplicationView* view) {
   view_ = view;
   DVLOG(1) << __FUNCTION__;
-  globals.main_thread_id = ::GetCurrentThreadId();
-
   HRESULT hr = view_->add_Activated(mswr::Callback<ActivatedHandler>(
       this, &ChromeAppViewAsh::OnActivate).Get(),
       &activated_token_);
@@ -298,9 +295,17 @@ IFACEMETHODIMP
 ChromeAppViewAsh::SetWindow(winui::Core::ICoreWindow* window) {
   window_ = window;
   DVLOG(1) << __FUNCTION__;
+
+  // Retrieve the native window handle via the interop layer.
+  mswr::ComPtr<ICoreWindowInterop> interop;
+  HRESULT hr = window->QueryInterface(interop.GetAddressOf());
+  CheckHR(hr);
+  hr = interop->get_WindowHandle(&core_window_hwnd_);
+  CheckHR(hr);
+
   // Register for pointer and keyboard notifications. We forward
   // them to the browser process via IPC.
-  HRESULT hr = window_->add_PointerMoved(mswr::Callback<PointerEventHandler>(
+  hr = window_->add_PointerMoved(mswr::Callback<PointerEventHandler>(
       this, &ChromeAppViewAsh::OnPointerMoved).Get(),
       &pointermoved_token_);
   CheckHR(hr);
@@ -376,10 +381,9 @@ ChromeAppViewAsh::Run() {
   CheckHR(hr, "Dispatcher failed.");
 
   hr = window_->Activate();
-  if (SUCCEEDED(hr)) {
-    // TODO(cpu): Draw something here.
-  } else {
-    DVLOG(1) << "Activate failed, hr=" << hr;
+  if (FAILED(hr)) {
+    DLOG(WARNING) << "activation failed hr=" << hr;
+    return hr;
   }
 
   // Create a message loop to allow message passing into this thread.
@@ -410,9 +414,11 @@ ChromeAppViewAsh::Run() {
                                io_thread.message_loop_proxy());
   ui_channel_ = &ui_channel;
 
+  // Upon receipt of the MetroViewerHostMsg_SetTargetSurface message the
+  // browser will use D3D from the browser process to present to our Window.
   ui_channel_->Send(new MetroViewerHostMsg_SetTargetSurface(
-                    gfx::NativeViewId(globals.core_window)));
-  DVLOG(1) << "ICoreWindow sent " << globals.core_window;
+                    gfx::NativeViewId(core_window_hwnd_)));
+  DVLOG(1) << "ICoreWindow sent " << core_window_hwnd_;
 
   // And post the task that'll do the inner Metro message pumping to it.
   msg_loop.PostTask(FROM_HERE, base::Bind(&RunMessageLoop, dispatcher.Get()));
@@ -427,6 +433,7 @@ ChromeAppViewAsh::Uninitialize() {
   DVLOG(1) << __FUNCTION__;
   window_ = nullptr;
   view_ = nullptr;
+  core_window_hwnd_ = NULL;
   return S_OK;
 }
 
@@ -526,20 +533,13 @@ HRESULT ChromeAppViewAsh::OnActivate(
     winapp::Core::ICoreApplicationView*,
     winapp::Activation::IActivatedEventArgs* args) {
   DVLOG(1) << __FUNCTION__;
-
+  // Note: If doing more work in this function, you migth need to call
+  // get_PreviousExecutionState() and skip the work if  the result is
+  // ApplicationExecutionState_Running and globals.previous_state is too.
   args->get_PreviousExecutionState(&globals.previous_state);
   DVLOG(1) << "Previous Execution State: " << globals.previous_state;
 
   window_->Activate();
-
-  if (globals.previous_state ==
-      winapp::Activation::ApplicationExecutionState_Running) {
-    DVLOG(1) << "Already running. Skipping rest of OnActivate.";
-    return S_OK;
-  }
-
-  globals.core_window =
-      winrt_utils::FindCoreWindow(globals.main_thread_id, 10);
   return S_OK;
 }
 
diff --git a/win8/metro_driver/chrome_app_view_ash.h b/win8/metro_driver/chrome_app_view_ash.h
index c13f757..6952d3d 100644
--- a/win8/metro_driver/chrome_app_view_ash.h
+++ b/win8/metro_driver/chrome_app_view_ash.h
@@ -114,9 +114,14 @@ class ChromeAppViewAsh
   // events do not contain that state, but Ash's MouseEvents need it.
   ui::EventFlags mouse_down_flags_;
 
+  // Set the D3D swap chain and nothing else.
   metro_driver::Direct3DHelper direct3d_helper_;
 
+  // The channel to Chrome, in particular to the MetroViewerProcessHost.
   IPC::ChannelProxy* ui_channel_;
+
+  // The actual window behind the view surface.
+  HWND core_window_hwnd_;
 };
 
 #endif  // WIN8_METRO_DRIVER_CHROME_APP_VIEW_ASH_H_