Replace merge-ui-and-compositor-threads flag with no-merge-ui-and-compositor-threads flag

android_webview/lib/main/aw_main_delegate.cc

Index: android_webview/lib/main/aw_main_delegate.cc
diff --git a/android_webview/lib/main/aw_main_delegate.cc b/android_webview/lib/main/aw_main_delegate.cc
index aba8ae3976913cb5ac05c2214d0f1334caa7e3dc..32afc03790db6d3eb52dd28b2e6c63eb1d155ae8 100644
--- a/android_webview/lib/main/aw_main_delegate.cc
+++ b/android_webview/lib/main/aw_main_delegate.cc
@@ -6,6 +6,7 @@
 
 #include "android_webview/browser/aw_content_browser_client.h"
 #include "android_webview/browser/in_process_renderer/in_process_renderer_client.h"
+#include "android_webview/browser/scoped_allow_wait_for_legacy_web_view_api.h"
 #include "android_webview/common/aw_switches.h"
 #include "android_webview/lib/aw_browser_dependency_factory_impl.h"
 #include "android_webview/native/aw_geolocation_permission_context.h"
@@ -13,6 +14,7 @@
 #include "android_webview/native/aw_web_contents_view_delegate.h"
 #include "android_webview/renderer/aw_content_renderer_client.h"
 #include "base/command_line.h"
+#include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/public/browser/browser_main_runner.h"
@@ -22,6 +24,17 @@
 
 namespace android_webview {
 
+namespace {
+
+base::LazyInstance<scoped_ptr<ScopedAllowWaitForLegacyWebViewApi> >
+    g_allow_wait_in_ui_thread = LAZY_INSTANCE_INITIALIZER;
+
+bool UIAndRendererCompositorThreadsNotMerged() {
+  return CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kNoMergeUIAndRendererCompositorThreads);
+}
+}
+
 AwMainDelegate::AwMainDelegate() {
 }
 
@@ -35,13 +48,12 @@ bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
       ::EnableVirtualizedContext();
 
   CommandLine* cl = CommandLine::ForCurrentProcess();
-  // Set the command line to enable synchronous API compatibility.
-  if (cl->HasSwitch(switches::kMergeUIAndRendererCompositorThreads)) {
-    cl->AppendSwitch(switches::kEnableSynchronousRendererCompositor);
-  } else {
+  if (UIAndRendererCompositorThreadsNotMerged()) {
     cl->AppendSwitch(switches::kEnableWebViewSynchronousAPIs);
+  } else {
+    // Set the command line to enable synchronous API compatibility.
+    cl->AppendSwitch(switches::kEnableSynchronousRendererCompositor);
   }
-
   return false;
 }
 
@@ -64,6 +76,12 @@ int AwMainDelegate::RunProcess(
     int exit_code = browser_runner_->Initialize(main_function_params);
     DCHECK(exit_code < 0);
 
+    // This is temporary until we remove the browser compositor
+    if (!UIAndRendererCompositorThreadsNotMerged()) {
+      g_allow_wait_in_ui_thread.Get().reset(
+          new ScopedAllowWaitForLegacyWebViewApi());
+    }
+
     // Return 0 so that we do NOT trigger the default behavior. On Android, the
     // UI message loop is managed by the Java application.
     return 0;
@@ -90,12 +108,10 @@ content::ContentRendererClient*
   DCHECK(CommandLine::ForCurrentProcess()->HasSwitch(switches::kSingleProcess));
   // During transition period allow running in either threading mode; eventually
   // only the compositor/UI thread merge mode will be supported.
-  const bool merge_threads =
-      CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kMergeUIAndRendererCompositorThreads);
+  const bool no_merge_threads = UIAndRendererCompositorThreadsNotMerged();
   content_renderer_client_.reset(
-      merge_threads ? new InProcessRendererClient() :
-                      new AwContentRendererClient());
+      no_merge_threads ? new AwContentRendererClient() :
+                         new InProcessRendererClient());
   return content_renderer_client_.get();
 }