Revert of Streamline frame detach

Source/core/page/Page.h

Index: Source/core/page/Page.h
diff --git a/Source/core/page/Page.h b/Source/core/page/Page.h
index 9da896b3381744e891752622dcc107efe3470d08..c0bf5bfe39e49f0ed6242e56dd4639fb18a395a5 100644
--- a/Source/core/page/Page.h
+++ b/Source/core/page/Page.h
@@ -134,6 +134,10 @@
     bool openedByDOM() const;
     void setOpenedByDOM();
 
+    void incrementSubframeCount() { ++m_subframeCount; }
+    void decrementSubframeCount() { ASSERT(m_subframeCount); --m_subframeCount; }
+    int subframeCount() const { checkSubframeCountConsistency(); return m_subframeCount; }
+
     PageAnimator& animator() { return m_animator; }
     Chrome& chrome() const { return *m_chrome; }
     AutoscrollController& autoscrollController() const { return *m_autoscrollController; }
@@ -181,6 +185,12 @@
     StorageNamespace* sessionStorage(bool optionalCreate = true);
     StorageClient& storageClient() const { return *m_storageClient; }
 
+    // Don't allow more than a certain number of frames in a page.
+    // This seems like a reasonable upper bound, and otherwise mutually
+    // recursive frameset pages can quickly bring the program to its knees
+    // with exponential growth in the number of frames.
+    static const int maxNumberOfFrames = 1000;
+
     PageVisibilityState visibilityState() const;
     void setVisibilityState(PageVisibilityState, bool);
 
@@ -217,6 +227,12 @@
 
 private:
     void initGroup();
+
+#if ENABLE(ASSERT)
+    void checkSubframeCountConsistency() const;
+#else
+    void checkSubframeCountConsistency() const { }
+#endif
 
     void setTimerAlignmentInterval(double);
 
@@ -261,6 +277,7 @@
 
     UseCounter m_useCounter;
 
+    int m_subframeCount;
     bool m_openedByDOM;
 
     bool m_tabKeyCyclesThroughElements;