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..c0217b82df91fe79d76a2e219f23b881786c2702 100644
--- a/content/browser/gpu/gpu_data_manager_impl_private.cc
+++ b/content/browser/gpu/gpu_data_manager_impl_private.cc
@@ -573,8 +573,27 @@ void GpuDataManagerImplPrivate::UpdateGpuInfoHelper() {
     gpu_driver_bugs_ = gpu_driver_bug_list_->MakeDecision(
         gpu::GpuControlList::kOsAny, std::string(), gpu_info_);
 
+    std::set<std::string> disabled_ext_set;
+
+    // Merge disabled extensions from the command line with gpu driver bug list.
+    const base::CommandLine* command_line =
+        base::CommandLine::ForCurrentProcess();
+    if (command_line) {
+      const std::vector<std::string>& disabled_command_line_exts =
+          base::SplitString(
+              command_line->GetSwitchValueASCII(switches::kDisableGLExtensions),
+              ", ;", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
+      disabled_ext_set.insert(disabled_command_line_exts.begin(),
+                              disabled_command_line_exts.end());
+    }
+    const std::vector<std::string>& disabled_driver_bug_exts =
+        gpu_driver_bug_list_->GetDisabledExtensions();
+    disabled_ext_set.insert(disabled_driver_bug_exts.begin(),
+                            disabled_driver_bug_exts.end());
     disabled_extensions_ =
-        base::JoinString(gpu_driver_bug_list_->GetDisabledExtensions(), " ");
+        base::JoinString(std::vector<std::string>(disabled_ext_set.begin(),
+                                                  disabled_ext_set.end()),
+                         " ");
   }
   gpu::GpuDriverBugList::AppendWorkaroundsFromCommandLine(
       &gpu_driver_bugs_, *base::CommandLine::ForCurrentProcess());
@@ -918,7 +937,6 @@ bool GpuDataManagerImplPrivate::ShouldDisableAcceleratedVideoDecode(
 void GpuDataManagerImplPrivate::GetDisabledExtensions(
     std::string* disabled_extensions) const {
   DCHECK(disabled_extensions);
-
   *disabled_extensions = disabled_extensions_;
 }