[OriginTrials] Don't attempt to initialize origin trials in isolated worlds.

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

Index: third_party/WebKit/Source/bindings/core/v8/WindowProxy.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/WindowProxy.cpp b/third_party/WebKit/Source/bindings/core/v8/WindowProxy.cpp
index 0ad555276d7f6fdbcad626cc62538a9f75d264e6..c6cb29661fc2cab3797a97d98c6bc06d8cc97012 100644
--- a/third_party/WebKit/Source/bindings/core/v8/WindowProxy.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/WindowProxy.cpp
@@ -272,11 +272,13 @@ bool WindowProxy::initialize()
     }
     // If Origin Trials have been registered before the V8 context was ready,
     // then inject them into the context now
-    ExecutionContext* executionContext = m_scriptState->getExecutionContext();
-    if (executionContext) {
-        OriginTrialContext* originTrialContext = OriginTrialContext::from(executionContext);
-        if (originTrialContext)
-            originTrialContext->initializePendingFeatures();
+    if (m_world->isMainWorld()) {
+        ExecutionContext* executionContext = m_scriptState->getExecutionContext();
+        if (executionContext) {
+            OriginTrialContext* originTrialContext = OriginTrialContext::from(executionContext);
+            if (originTrialContext)
+                originTrialContext->initializePendingFeatures();
+        }
     }
     return true;
 }