Implement pointer lock API for out-of-process iframes.

third_party/WebKit/Source/core/dom/Document.cpp

Index: third_party/WebKit/Source/core/dom/Document.cpp
diff --git a/third_party/WebKit/Source/core/dom/Document.cpp b/third_party/WebKit/Source/core/dom/Document.cpp
index ca2a90e19217082b68f6e8b8d71b404e40560d79..9c74068055897d0e2168a1b1735c28d2907d3830 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -5316,8 +5316,8 @@ void Document::exitPointerLock()
     if (Element* target = page()->pointerLockController().element()) {
         if (target->document() != this)
             return;
+        page()->pointerLockController().requestPointerUnlock();
     }
-    page()->pointerLockController().requestPointerUnlock();
 }
 
 Element* Document::pointerLockElement() const