Make FeatureList override state be plumbed to renderer processes.

content/browser/renderer_host/render_process_host_impl.cc

 // Copyright 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.
 
 // Represents the browser side of the browser <--> renderer communication
 // channel. There will be one RenderProcessHost per renderer process.
 
 #include "content/browser/renderer_host/render_process_host_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <vector>
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/debug/dump_without_crashing.h"
+#include "base/feature_list.h"
 #include "base/files/file.h"
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/process/process_handle.h"
 #include "base/rand_util.h"
 #include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
@@ skipping 396 matching lines @@
 std::string UintVectorToString(const std::vector<unsigned>& vector) {
   std::string str;
   for (auto it : vector) {
     if (!str.empty())
       str += ",";
     str += base::UintToString(it);
   }
   return str;
 }
 
+// Copies kEnableFeatures and kDisableFeatures to the renderer command line.
+// Generates them from the FeatureList override state, to take into account
+// overrides from FieldTrials.
+void CopyEnableDisableFeatureFlagsToRenderer(base::CommandLine* renderer_cmd) {
+  std::string enabled_features;
+  std::string disabled_features;
+  base::FeatureList::GetInstance()->GetFeatureOverrides(&enabled_features,
+                                                        &disabled_features);
+  if (!enabled_features.empty()) {
+    renderer_cmd->AppendSwitchASCII(switches::kEnableFeatures,
+                                    enabled_features);
+  }
+  if (!disabled_features.empty()) {
+    renderer_cmd->AppendSwitchASCII(switches::kDisableFeatures,
+                                    disabled_features);
+  }
+}
+
 }  // namespace
 
 RendererMainThreadFactoryFunction g_renderer_main_thread_factory = NULL;
 
 base::MessageLoop* g_in_process_thread;
 
 base::MessageLoop*
 RenderProcessHostImpl::GetInProcessRendererThreadForTesting() {
   return g_in_process_thread;
 }
@@ skipping 849 matching lines @@
     switches::kDisableAcceleratedVideoDecode,
     switches::kDisableBlinkFeatures,
     switches::kDisableBreakpad,
     switches::kDisablePreferCompositingToLCDText,
     switches::kDisableDatabases,
     switches::kDisableDelayAgnosticAec,
     switches::kDisableDirectNPAPIRequests,
     switches::kDisableDisplayList2dCanvas,
     switches::kDisableDistanceFieldText,
     switches::kDisableEncryptedMedia,
-    switches::kDisableFeatures,
     switches::kDisableFileSystem,
     switches::kDisableGestureRequirementForMediaPlayback,
     switches::kDisableGpuCompositing,
     switches::kDisableGpuMemoryBufferVideoFrames,
     switches::kDisableGpuVsync,
     switches::kDisableLowResTiling,
     switches::kDisableHistogramCustomizer,
     switches::kDisableIconNtp,
     switches::kDisableLCDText,
     switches::kDisableLocalStorage,
@@ skipping 18 matching lines @@
     switches::kDisableV8IdleTasks,
     switches::kDomAutomationController,
     switches::kEnableBlinkFeatures,
     switches::kEnableBrowserSideNavigation,
     switches::kEnableCompositorAnimationTimelines,
     switches::kEnableCredentialManagerAPI,
     switches::kEnableDisplayList2dCanvas,
     switches::kEnableDistanceFieldText,
     switches::kEnableExperimentalCanvasFeatures,
     switches::kEnableExperimentalWebPlatformFeatures,
-    switches::kEnableFeatures,
     switches::kEnableHeapProfiling,
     switches::kEnableGPUClientLogging,
     switches::kEnableGpuClientTracing,
     switches::kEnableGpuMemoryBufferVideoFrames,
     switches::kEnableGPUServiceLogging,
     switches::kEnableIconNtp,
     switches::kEnableLinkDisambiguationPopup,
     switches::kEnableLowResTiling,
     switches::kEnableInbandTextTracks,
     switches::kEnableLCDText,
@@ skipping 121 matching lines @@
     switches::kOzonePlatform,
 #endif
 #if defined(OS_CHROMEOS)
     switches::kDisableVaapiAcceleratedVideoEncode,
 #endif
     "use-new-edk",  // TODO(use_chrome_edk): temporary.
   };
   renderer_cmd->CopySwitchesFrom(browser_cmd, kSwitchNames,
                                  arraysize(kSwitchNames));
 
+  CopyEnableDisableFeatureFlagsToRenderer(renderer_cmd);
+
   if (browser_cmd.HasSwitch(switches::kTraceStartup) &&
       BrowserMainLoop::GetInstance()->is_tracing_startup_for_duration()) {
     // Pass kTraceStartup switch to renderer only if startup tracing has not
     // finished.
     renderer_cmd->AppendSwitchASCII(
         switches::kTraceStartup,
         browser_cmd.GetSwitchValueASCII(switches::kTraceStartup));
   }
 
 #if defined(ENABLE_WEBRTC)
@@ skipping 1123 matching lines @@
 void RenderProcessHostImpl::GetAudioOutputControllers(
     const GetAudioOutputControllersCallback& callback) const {
   audio_renderer_host()->GetOutputControllers(callback);
 }
 
 BluetoothDispatcherHost* RenderProcessHostImpl::GetBluetoothDispatcherHost() {
   return bluetooth_dispatcher_host_.get();
 }
 
 }  // namespace content