bug 1271436 - use nsIDocShellTreeItem::GetDocument() more r=smaug

docshell/base/nsDocShell.cpp

@@ -9973,7 +9973,7 @@ nsDocShell::InternalLoad(nsIURI* aURI,
   // possible frameloader initialization before loading a new page.
   nsCOMPtr<nsIDocShellTreeItem> parent = GetParentDocshell();
   if (parent) {
-    nsCOMPtr<nsIDocument> doc = do_GetInterface(parent);
+    nsCOMPtr<nsIDocument> doc = parent->GetDocument();
     if (doc) {
       doc->TryCancelFrameLoaderInitialization(this);
     }

dom/base/nsDocument.cpp

@@ -2495,7 +2495,7 @@ WarnIfSandboxIneffective(nsIDocShell* aDocShell,
       return;
     }
 
-    nsCOMPtr<nsIDocument> parentDocument = do_GetInterface(parentDocShell);
+    nsCOMPtr<nsIDocument> parentDocument = parentDocShell->GetDocument();
     nsCOMPtr<nsIURI> iframeUri;
     parentChannel->GetURI(getter_AddRefs(iframeUri));
     nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,

dom/base/nsFrameLoader.cpp

@@ -3237,7 +3237,8 @@ nsFrameLoader::StartPersistence(uint64_t aOuterWindowID,
     return mRemoteBrowser->StartPersistence(aOuterWindowID, aRecv);
   }
 
-  nsCOMPtr<nsIDocument> rootDoc = do_GetInterface(mDocShell);
+  nsCOMPtr<nsIDocument> rootDoc =
+    mDocShell ? mDocShell->GetDocument() : nullptr;
   nsCOMPtr<nsIDocument> foundDoc;
   if (aOuterWindowID) {
     foundDoc = nsContentUtils::GetSubdocumentWithOuterWindowId(rootDoc, aOuterWindowID);

dom/security/nsMixedContentBlocker.cpp

@@ -87,7 +87,7 @@ public:
     NS_ASSERTION(sameTypeRoot, "No document shell root tree item from document shell tree item!");
 
     // now get the document from sameTypeRoot
-    nsCOMPtr<nsIDocument> rootDoc = do_GetInterface(sameTypeRoot);
+    nsCOMPtr<nsIDocument> rootDoc = sameTypeRoot->GetDocument();
     NS_ASSERTION(rootDoc, "No root document from document shell root tree item.");
 
     // Get eventSink and the current security state from the docShell
@@ -764,7 +764,7 @@ nsMixedContentBlocker::ShouldLoad(bool aHadInsecureImageRedirect,
   }
 
   // Get the root document from the sameTypeRoot
-  nsCOMPtr<nsIDocument> rootDoc = do_GetInterface(sameTypeRoot);
+  nsCOMPtr<nsIDocument> rootDoc = sameTypeRoot->GetDocument();
   NS_ASSERTION(rootDoc, "No root document from document shell root tree item.");
 
   // Get eventSink and the current security state from the docShell

netwerk/base/nsChannelClassifier.cpp

@@ -231,8 +231,8 @@ nsChannelClassifier::NotifyTrackingProtectionDisabled(nsIChannel *aChannel)
     if (!docShell) {
       return NS_OK;
     }
-    nsCOMPtr<nsIDocument> doc = do_GetInterface(docShell, &rv);
-    NS_ENSURE_SUCCESS(rv, NS_OK);
+    nsCOMPtr<nsIDocument> doc = docShell->GetDocument();
+    NS_ENSURE_TRUE(doc, NS_OK);
 
     // Notify nsIWebProgressListeners of this security event.
     // Can be used to change the UI state.
@@ -543,8 +543,8 @@ nsChannelClassifier::SetBlockedTrackingContent(nsIChannel *channel)
   if (!docShell) {
     return NS_OK;
   }
-  nsCOMPtr<nsIDocument> doc = do_GetInterface(docShell, &rv);
-  NS_ENSURE_SUCCESS(rv, NS_OK);
+  nsCOMPtr<nsIDocument> doc = docShell->GetDocument();
+  NS_ENSURE_TRUE(doc, NS_OK);
 
   // This event might come after the user has navigated to another page.
   // To prevent showing the TrackingProtection UI on the wrong page, we need to