Make gpu black list work again on Linux

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index b264d2070d447470b61e36a69f4a7a746825b9c2..ce74ff896d8e9ebc41634a7c53795b2566982eca 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -1132,6 +1132,23 @@ int ChromeBrowserMainParts::PreCreateThreadsImpl() {
   return content::RESULT_CODE_NORMAL_EXIT;
 }
 
+void ChromeBrowserMainParts::PreCreateThreadsEnd() {
+  // GpuDataManagerImpl::GetInstance()->Initialize(); is called at the end of
+  // BrowserMainLoop::PreCreateThreads() so it is wrong to call the 2 following
+  // function in this->PreCreateThreads(). Otherwise it will access the gpu
+  // data manager before initializing it.
+  // Alternatively we could ensure that content::GpuDataManager::GetInstance()

[Zhenyao Mo, 2016/01/05 18:04:44]

No, we want to be explicit where and when Initialize() happens.

Otherwise who knows what kind of bugs may sneak into this mechanism.

Please remove this last "Alternatively" comment.

It's really sad the gl_string_manager initialization got moved to the wrong
place.

To prevent this from happening again, what we probably could do is to add a
initialized_ member in GpuDataManagerImpl and DCHECK in GetInstance() that it's
already initialized.

+  // internally calls GpuDataManagerImpl::GetInstance()->Initialize().
+
+  // Retrieve cached GL strings from local state and use them for GPU
+  // blacklist decisions.
+  if (g_browser_process->gl_string_manager())
+    g_browser_process->gl_string_manager()->Initialize();
+
+  // Create an instance of GpuModeManager to watch gpu mode pref change.
+  g_browser_process->gpu_mode_manager();
+}
+
 void ChromeBrowserMainParts::PreMainMessageLoopRun() {
   TRACE_EVENT0("startup", "ChromeBrowserMainParts::PreMainMessageLoopRun");
   TRACK_SCOPED_REGION(
@@ -1502,14 +1519,6 @@ int ChromeBrowserMainParts::PreMainMessageLoopRunImpl() {
   // (requires supporting early exit).
   PostProfileInit();
 
-  // Retrieve cached GL strings from local state and use them for GPU
-  // blacklist decisions.
-  if (g_browser_process->gl_string_manager())
-    g_browser_process->gl_string_manager()->Initialize();
-
-  // Create an instance of GpuModeManager to watch gpu mode pref change.
-  g_browser_process->gpu_mode_manager();
-
 #if !defined(OS_ANDROID) && !defined(OS_CHROMEOS)
   // Show the First Run UI if this is the first time Chrome has been run on
   // this computer, or we're being compelled to do so by a command line flag.