Bug 805670 - Introduce nsIDOMWindowUtils.getResolution. r=dholbert sr=smaug

dom/base/nsDOMWindowUtils.cpp

@@ -414,6 +414,23 @@ nsDOMWindowUtils::SetResolution(float aXResolution, float aYResolution)
                    : NS_ERROR_FAILURE;
 }
 
+NS_IMETHODIMP
+nsDOMWindowUtils::GetResolution(float* aXResolution, float* aYResolution)
+{
+  if (!nsContentUtils::IsCallerChrome()) {
+    return NS_ERROR_DOM_SECURITY_ERR;
+  }
+
+  nsIPresShell* presShell = GetPresShell();
+
+  if (presShell) {
+    *aXResolution = presShell->GetXResolution();
+    *aYResolution = presShell->GetYResolution();
+    return NS_OK;
+  }
+  return NS_ERROR_FAILURE;
+}
+
 NS_IMETHODIMP
 nsDOMWindowUtils::SetIsFirstPaint(bool aIsFirstPaint)
 {

dom/interfaces/base/nsIDOMWindowUtils.idl

@@ -40,7 +40,7 @@ interface nsIDOMTouch;
 interface nsIDOMClientRect;
 interface nsIURI;
 
-[scriptable, uuid(020deb5a-cba6-41dd-8551-72a880d01970)]
+[scriptable, uuid(b3a3589d-cc9d-4123-9b21-51c66e88b436)]
 interface nsIDOMWindowUtils : nsISupports {
 
   /**
@@ -174,6 +174,8 @@ interface nsIDOMWindowUtils : nsISupports {
    */
   void setResolution(in float aXResolution, in float aYResolution);
 
+  void getResolution(out float aXResolution, out float aYResolution);
+
   /**
    * Whether the next paint should be flagged as the first paint for a document.
    * This gives a way to track the next paint that occurs after the flag is