Move code to register/unregister memory dump provider from blink::initialize/shutdown

third_party/WebKit/Source/platform/exported/Platform.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "base/thread_task_runner_handle.h"
 #include "base/trace_event/memory_dump_manager.h"
 #include "platform/PartitionAllocMemoryDumpProvider.h"
+#include "platform/fonts/FontCacheMemoryDumpProvider.h"
 #include "platform/graphics/CompositorFactory.h"
 #include "platform/web_memory_dump_provider_adapter.h"
 #include "public/platform/Platform.h"
 #include "wtf/HashMap.h"
 #include "wtf/OwnPtr.h"
 
 namespace blink {
 
 static Platform* s_platform = 0;
 using ProviderToAdapterMap = HashMap<WebMemoryDumpProvider*, OwnPtr<WebMemoryDumpProviderAdapter>>;
@@ skipping 17 matching lines @@
 {
     s_platform = platform;
     if (s_platform)
         s_platform->m_mainThread = platform->currentThread();
 
     // TODO(ssid): remove this check after fixing crbug.com/486782.
     if (s_platform && s_platform->m_mainThread)
         s_platform->registerMemoryDumpProvider(PartitionAllocMemoryDumpProvider::instance(), "PartitionAlloc");
 
     CompositorFactory::initializeDefault();
+    platform->registerMemoryDumpProvider(FontCacheMemoryDumpProvider::instance(), "FontCaches");

[sof, 2016/03/10 07:40:12]

So what is the status of |platform|, can it be non-null or not? We assume
differently in this method.

 }
 
 void Platform::shutdown()
 {
+    s_platform->unregisterMemoryDumpProvider(FontCacheMemoryDumpProvider::instance());
     CompositorFactory::shutdown();
 
     if (s_platform->m_mainThread)
         s_platform->unregisterMemoryDumpProvider(PartitionAllocMemoryDumpProvider::instance());
 
     if (s_platform)
         s_platform->m_mainThread = 0;
     s_platform = 0;
 }
 
 Platform* Platform::current()
 {
     return s_platform;
 }
 
 WebThread* Platform::mainThread() const
 {
     return m_mainThread;
 }
 
 void Platform::registerMemoryDumpProvider(WebMemoryDumpProvider* provider, const char* name)
 {
+    // MemoryDumpProvider needs a message loop.
+    if (!Platform::current()->currentThread())
+        return;
+
     WebMemoryDumpProviderAdapter* adapter = new WebMemoryDumpProviderAdapter(provider);
     ProviderToAdapterMap::AddResult result = memoryDumpProviders().add(provider, adoptPtr(adapter));
     if (!result.isNewEntry)
         return;
     adapter->set_is_registered(true);
     base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(adapter, name, base::ThreadTaskRunnerHandle::Get());
 }
 
 void Platform::unregisterMemoryDumpProvider(WebMemoryDumpProvider* provider)
 {
+    // MemoryDumpProvider needs a message loop.
+    if (!Platform::current()->currentThread())
+        return;
+
     ProviderToAdapterMap::iterator it = memoryDumpProviders().find(provider);
     if (it == memoryDumpProviders().end())
         return;
     WebMemoryDumpProviderAdapter* adapter = it->value.get();
     base::trace_event::MemoryDumpManager::GetInstance()->UnregisterDumpProvider(adapter);
     adapter->set_is_registered(false);
     memoryDumpProviders().remove(it);
 }
 
 } // namespace blink