Fix disabled extensions for virtual contexts and respect command line.

content/browser/gpu/gpu_data_manager_impl_private.cc

Index: content/browser/gpu/gpu_data_manager_impl_private.cc
diff --git a/content/browser/gpu/gpu_data_manager_impl_private.cc b/content/browser/gpu/gpu_data_manager_impl_private.cc
index ec1776cd4b31b9b23bab96e8e19a17ef3d304154..4da299b1b94f3527ec62ad6f4013fad73ce1b3a2 100644
--- a/content/browser/gpu/gpu_data_manager_impl_private.cc
+++ b/content/browser/gpu/gpu_data_manager_impl_private.cc
@@ -573,8 +573,23 @@ void GpuDataManagerImplPrivate::UpdateGpuInfoHelper() {
     gpu_driver_bugs_ = gpu_driver_bug_list_->MakeDecision(
         gpu::GpuControlList::kOsAny, std::string(), gpu_info_);
 
-    disabled_extensions_ =
-        base::JoinString(gpu_driver_bug_list_->GetDisabledExtensions(), " ");
+    std::vector<std::string> disabled_vec;
+
+    const base::CommandLine* command_line =
+        base::CommandLine::ForCurrentProcess();
+    if (command_line) {
+      disabled_vec = base::SplitString(
+          command_line->GetSwitchValueASCII(switches::kDisableGLExtensions),
+          ", ;",
+          base::KEEP_WHITESPACE,
+          base::SPLIT_WANT_NONEMPTY);
+    }
+    const std::vector<std::string>& disabled_driver_bug_exts =
+        gpu_driver_bug_list_->GetDisabledExtensions();
+    disabled_vec.insert(disabled_vec.end(),

[Zhenyao Mo, 2015/12/03 23:28:10]

Here you may insert the same extension twice if it's specified in the
commandline and also by the driver_bug_list.

[David Yen, 2015/12/04 00:10:53]

Done.

+                        disabled_driver_bug_exts.begin(),
+                        disabled_driver_bug_exts.end());
+    disabled_extensions_ = base::JoinString(disabled_vec, " ");
   }
   gpu::GpuDriverBugList::AppendWorkaroundsFromCommandLine(
       &gpu_driver_bugs_, *base::CommandLine::ForCurrentProcess());
@@ -918,7 +933,6 @@ bool GpuDataManagerImplPrivate::ShouldDisableAcceleratedVideoDecode(
 void GpuDataManagerImplPrivate::GetDisabledExtensions(
     std::string* disabled_extensions) const {
   DCHECK(disabled_extensions);
-
   *disabled_extensions = disabled_extensions_;
 }