Expose performance.memory in workers

Source/core/timing/MemoryInfo.cpp

Index: Source/core/timing/MemoryInfo.cpp
diff --git a/Source/core/timing/MemoryInfo.cpp b/Source/core/timing/MemoryInfo.cpp
index 3bb082123a1f4f7f7c7dcc44c19857dca484d686..fd421cbe3bfc78f9257b5f2d4ce5cbaa42369546 100644
--- a/Source/core/timing/MemoryInfo.cpp
+++ b/Source/core/timing/MemoryInfo.cpp
@@ -32,8 +32,10 @@
 #include "core/timing/MemoryInfo.h"
 
 #include <limits>
+#include "core/dom/Document.h"
 #include "core/frame/Frame.h"
 #include "core/frame/Settings.h"
+#include "core/workers/WorkerGlobalScope.h"
 #include "wtf/CurrentTime.h"
 #include "wtf/MainThread.h"
 #include "wtf/MathExtras.h"
@@ -132,13 +134,31 @@ size_t quantizeMemorySize(size_t size)
 }
 
 
-MemoryInfo::MemoryInfo(Frame* frame)
+MemoryInfo::MemoryInfo(ExecutionContext* context)
 {
     ScriptWrappable::init(this);
-    if (!frame || !frame->settings())
+
+    if (!context)
         return;
 
-    if (frame->settings()->memoryInfoEnabled()) {
+    if (context->isDocument()) {
+        Frame* frame = toDocument(context)->frame();
+        if (!frame || !frame->settings())
+            return;
+        loadMemoryInfo(frame->settings()->memoryInfoEnabled());
+    }
+
+    if (context->isWorkerGlobalScope()) {
+        WorkerGlobalScope* workerGlobalScope = toWorkerGlobalScope(context);
+        if (!workerGlobalScope)
+            return;
+        loadMemoryInfo(workerGlobalScope->memoryInfoEnabled());
+    }
+}
+
+void MemoryInfo::loadMemoryInfo(bool memoryInfoEnabled)
+{
+    if (memoryInfoEnabled) {
         ScriptGCEvent::getHeapSize(m_info);
     } else {
         DEFINE_STATIC_LOCAL(HeapSizeCache, heapSizeCache, ());