Adds Mojo IDL.

third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp

Index: third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp b/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
index b8e036990940bd6c1bcb5e18aee2afcea3b8871c..6e44b872d977d4297620dfe8437e139861c6addd 100644
--- a/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp
@@ -49,6 +49,7 @@
 #include "core/inspector/MainThreadDebugger.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
+#include "core/mojo/Mojo.h"
 #include "core/origin_trials/OriginTrialContext.h"
 #include "platform/Histogram.h"
 #include "platform/RuntimeEnabledFeatures.h"
@@ -120,14 +121,21 @@ void LocalWindowProxy::initialize() {
                                                  origin);
   frame()->loader().client()->didCreateScriptContext(context,
                                                      m_world->worldId());
-  // If conditional features for window have been queued before the V8 context
-  // was ready, then inject them into the context now
+
   if (m_world->isMainWorld()) {
+    if (RuntimeEnabledFeatures::mojoJSEnabled()) {
+      LOG(INFO) << "Installing mojo bindings";
+      v8::Local<v8::Object> global = context->Global();
+      v8::Local<v8::Value> mojo = ToV8(Mojo::create(), global, isolate());
+      global->Set(context, v8AtomicString(isolate(), "mojo"), mojo).ToChecked();
+    }
+
+    // If conditional features for window have been queued before the V8 context
+    // was ready, then inject them into the context now
     installPendingConditionalFeaturesOnWindow(m_scriptState.get());
-  }
 
-  if (m_world->isMainWorld())
     frame()->loader().dispatchDidClearWindowObjectInMainWorld();
+  }
 }
 
 void LocalWindowProxy::createContext() {