[DevTools] Force context creation when runtime is enabled.

third_party/WebKit/Source/core/inspector/PageRuntimeAgent.cpp

Index: third_party/WebKit/Source/core/inspector/PageRuntimeAgent.cpp
diff --git a/third_party/WebKit/Source/core/inspector/PageRuntimeAgent.cpp b/third_party/WebKit/Source/core/inspector/PageRuntimeAgent.cpp
index b10b2e612a8d512448c4efcbca060381cf5c2816..ca54c5c391c9a474c4a52e0dc339f1898a2d63dc 100644
--- a/third_party/WebKit/Source/core/inspector/PageRuntimeAgent.cpp
+++ b/third_party/WebKit/Source/core/inspector/PageRuntimeAgent.cpp
@@ -65,6 +65,9 @@ void PageRuntimeAgent::enable(ErrorString* errorString)
     if (m_enabled)
         return;
 
+    m_instrumentingAgents->setPageRuntimeAgent(this);
+    if (m_inspectedFrames->root()->loader().stateMachine()->committedFirstRealDocumentLoad())
+        m_inspectedFrames->root()->script().initializeMainWorld();
     InspectorRuntimeAgent::enable(errorString);
 }
 
@@ -73,6 +76,12 @@ void PageRuntimeAgent::disable(ErrorString* errorString)
     if (!m_enabled)
         return;
     InspectorRuntimeAgent::disable(errorString);
+    m_instrumentingAgents->setPageRuntimeAgent(nullptr);
+}
+
+void PageRuntimeAgent::didClearDocumentOfWindowObject(LocalFrame* frame)
+{
+    frame->script().initializeMainWorld();
 }
 
 } // namespace blink