[ChromeOS] Do not send the memory pressure notification from chrome to renderers

chrome/browser/memory/tab_manager.cc

 // Copyright (c) 2012 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 "chrome/browser/memory/tab_manager.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <set>
@@ skipping 653 matching lines @@
     LogMemoryAndDiscardTab();
   }
   // TODO(skuhne): If more memory pressure levels are introduced, consider
   // calling PurgeBrowserMemory() before CRITICAL is reached.
 
   // If this is the beginning of a period of memory pressure then kick off
   // notification of child processes.
   // NOTE: This mechanism relies on having a MemoryPressureMonitor
   // implementation that supports "CurrentPressureLevel". This is true on all
   // platforms on which TabManager is used.
+#if !defined(OS_CHROMEOS)
+  // Running GC under memory pressure can cause thrashing. Disable it on
+  // ChromeOS until the thrashing is fixed. crbug.com/588172.
   if (!under_memory_pressure_)
     DoChildProcessDispatch();
+#endif
 }
 
 bool TabManager::IsMediaTab(WebContents* contents) const {
   if (contents->WasRecentlyAudible())
     return true;
 
   scoped_refptr<MediaStreamCaptureIndicator> media_indicator =
       MediaCaptureDevicesDispatcher::GetInstance()
           ->GetMediaStreamCaptureIndicator();
   if (media_indicator->IsCapturingUserMedia(contents) ||
@@ skipping 114 matching lines @@
   // Schedule another notification. Use a weak pointer so this doesn't explode
   // during tear down.
   task_runner_->PostDelayedTask(
       FROM_HERE,
       base::Bind(&TabManager::DoChildProcessDispatch,
                  weak_ptr_factory_.GetWeakPtr()),
       base::TimeDelta::FromSeconds(kRendererNotificationDelayInSeconds));
 }
 
 }  // namespace memory