Fix flakiness in DumpAccessibilityEvent* tests.

content/browser/accessibility/accessibility_event_recorder_win.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/accessibility/accessibility_event_recorder.h"
 
 #include <oleacc.h>
 
 #include <string>
 
@@ skipping 77 matching lines @@
   // info about the node the event was fired on and appends a string to
   // the event log.
   void OnWinEventHook(HWINEVENTHOOK handle,
                       DWORD event,
                       HWND hwnd,
                       LONG obj_id,
                       LONG child_id,
                       DWORD event_thread,
                       DWORD event_time);
 
+  // Wrapper around AccessibleObjectFromWindow because the function call
+  // inexplicably flakes sometimes on build/trybots.
+  HRESULT AccessibleObjectFromWindowWrapper(
+      HWND hwnd, DWORD dwId, REFIID riid, void **ppvObject);
+
   HWINEVENTHOOK win_event_hook_handle_;
   static AccessibilityEventRecorderWin* instance_;
 };
 
 // static
 AccessibilityEventRecorderWin*
 AccessibilityEventRecorderWin::instance_ = nullptr;
 
 // static
 AccessibilityEventRecorder* AccessibilityEventRecorder::Create(
@@ skipping 23 matching lines @@
                     << " WinAccessibilityEventMonitor at a time.";
   instance_ = this;
   win_event_hook_handle_ = SetWinEventHook(
       EVENT_MIN,
       EVENT_MAX,
       GetModuleHandle(NULL),
       &AccessibilityEventRecorderWin::WinEventHookThunk,
       GetCurrentProcessId(),
       0,  // Hook all threads
       WINEVENT_INCONTEXT);
-  LOG(INFO) << "SetWinEventHook handle: " << win_event_hook_handle_;
   CHECK(win_event_hook_handle_);
 }
 
 AccessibilityEventRecorderWin::~AccessibilityEventRecorderWin() {
   UnhookWinEvent(win_event_hook_handle_);
   instance_ = NULL;
 }
 
 void AccessibilityEventRecorderWin::OnWinEventHook(
     HWINEVENTHOOK handle,
     DWORD event,
     HWND hwnd,
     LONG obj_id,
     LONG child_id,
     DWORD event_thread,
     DWORD event_time) {
-  // http://crbug.com/440579 TODO(dmazzoni): remove most logging in this file,
-  // or change to VLOG(1), once flakiness on CrWinClang testers is fixed.
-  LOG(INFO) << "OnWinEventHook handle=" << handle
-            << " event=" << event
-            << " hwnd=" << hwnd
-            << " obj_id=" << obj_id
-            << " child_id=" << child_id
-            << " event_thread=" << event_thread
-            << " event_time=" << event_time;
-
   base::win::ScopedComPtr<IAccessible> browser_accessible;
-  HRESULT hr = AccessibleObjectFromWindow(
+  HRESULT hr = AccessibleObjectFromWindowWrapper(
       hwnd,
       obj_id,
       IID_IAccessible,
       reinterpret_cast<void**>(browser_accessible.Receive()));
   if (!SUCCEEDED(hr)) {
     // Note: our event hook will pick up some superfluous events we
     // don't care about, so it's safe to just ignore these failures.
     // Same below for other HRESULT checks.
-    LOG(INFO) << "Ignoring result " << hr << " from AccessibleObjectFromWindow";
-    TCHAR name[MAX_PATH];
-    GetClassName(hwnd, name, _countof(name));
-    LOG(INFO) << "Hwnd " << hwnd << " class is " << name;
+    VLOG(1) << "Ignoring result " << hr << " from AccessibleObjectFromWindow";
     return;
   }
 
   base::win::ScopedVariant childid_variant(child_id);
   base::win::ScopedComPtr<IDispatch> dispatch;
   hr = browser_accessible->get_accChild(childid_variant, dispatch.Receive());
   if (!SUCCEEDED(hr) || !dispatch) {
-    LOG(INFO) << "Ignoring result " << hr << " and result " << dispatch
-              << " from get_accChild";
+    VLOG(1) << "Ignoring result " << hr << " and result " << dispatch
+            << " from get_accChild";
     return;
   }
 
   base::win::ScopedComPtr<IAccessible> iaccessible;
   hr = dispatch.QueryInterface(iaccessible.Receive());
   if (!SUCCEEDED(hr)) {
-    LOG(INFO) << "Ignoring result " << hr << " from QueryInterface";
+    VLOG(1) << "Ignoring result " << hr << " from QueryInterface";
     return;
   }
 
   std::string event_str = AccessibilityEventToStringUTF8(event);
   if (event_str.empty()) {
-    LOG(INFO) << "Ignoring event " << event;
+    VLOG(1) << "Ignoring event " << event;
     return;
   }
 
   base::win::ScopedVariant childid_self(CHILDID_SELF);
   base::win::ScopedVariant role;
   iaccessible->get_accRole(childid_self, role.Receive());
   base::win::ScopedBstr name_bstr;
   iaccessible->get_accName(childid_self, name_bstr.Receive());
   base::win::ScopedBstr value_bstr;
   iaccessible->get_accValue(childid_self, value_bstr.Receive());
@@ skipping 23 matching lines @@
       IA2TextSegment new_text;
       if (SUCCEEDED(accessible_text->get_newText(&new_text))) {
         log += base::StringPrintf(" new_text={'%s' start=%d end=%d}",
                                   BstrToUTF8(new_text.text).c_str(),
                                   new_text.start,
                                   new_text.end);
       }
     }
   }
 
-  LOG(INFO) << "Got event log: " << log;
-
   event_logs_.push_back(log);
 }
 
+HRESULT AccessibilityEventRecorderWin::AccessibleObjectFromWindowWrapper(
+    HWND hwnd, DWORD dw_id, REFIID riid, void** ppv_object) {
+  HRESULT hr = ::AccessibleObjectFromWindow(hwnd, dw_id, riid, ppv_object);
+  if (SUCCEEDED(hr))
+    return hr;
+
+  // The above call to ::AccessibleObjectFromWindow fails for unknown
+  // reasons every once in a while on the bots.  Work around it by grabbing
+  // the object directly from the BrowserAccessibilityManager.
+  HWND accessibility_hwnd =
+      manager_->delegate()->AccessibilityGetAcceleratedWidget();
+  if (accessibility_hwnd != hwnd)
+    return E_FAIL;
+
+  IAccessible* obj = manager_->GetRoot()->ToBrowserAccessibilityWin();
+  obj->AddRef();
+  *ppv_object = obj;
+  return S_OK;
+}
+
 }  // namespace content