Implement renderer importance API for WebView

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>
@@ skipping 2788 matching lines @@
 void RenderProcessHostImpl::SuddenTerminationChanged(bool enabled) {
   SetSuddenTerminationAllowed(enabled);
 }
 
 void RenderProcessHostImpl::UpdateProcessPriority() {
   if (!child_process_launcher_.get() || child_process_launcher_->IsStarting()) {
     is_process_backgrounded_ = false;
     return;
   }
 
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDisableRendererPriorityManagement)) {
+    return;
+  }
+
   // We background a process as soon as it hosts no active audio streams and no
   // visible widgets -- the callers must call this function whenever we
   // transition in/out of those states.
   const bool should_background =
       visible_widgets_ == 0 && !audio_renderer_host_->HasActiveAudio() &&
       !base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kDisableRendererBackgrounding);
 
 // TODO(sebsg): Remove this ifdef when https://crbug.com/537671 is fixed.
 #if !defined(OS_ANDROID)
@@ skipping 233 matching lines @@
   LOG(ERROR) << "Terminating render process for bad Mojo message: " << error;
 
   // The ReceivedBadMessage call below will trigger a DumpWithoutCrashing.
   // Capture the error message in a crash key value.
   base::debug::ScopedCrashKey error_key_value("mojo-message-error", error);
   bad_message::ReceivedBadMessage(render_process_id,
                                   bad_message::RPH_MOJO_PROCESS_ERROR);
 }
 
 }  // namespace content