Bug 714346. Part 1. Make some code stop checking useless return values because it makes the control flow more complicated then needed. r=mats

layout/generic/nsSubDocumentFrame.cpp

@@ -343,7 +343,7 @@ nsSubDocumentFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
   nsRect subdocBoundsInParentUnits =
     mInnerView->GetBounds() + GetOffsetToCrossDoc(aBuilder->ReferenceFrame());
 
-  if (subdocRootFrame && NS_SUCCEEDED(rv)) {
+  if (subdocRootFrame) {
     rv = subdocRootFrame->
            BuildDisplayListForStackingContext(aBuilder, dirty, &childItems);
   }
@@ -378,42 +378,39 @@ nsSubDocumentFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
     }
   }
 
-  if (NS_SUCCEEDED(rv)) {
+  bool addedLayer = false;
 
-    bool addedLayer = false;
+  if (subdocRootFrame && parentAPD != subdocAPD) {
+    NS_WARN_IF_FALSE(!addedLayer,
+                     "Two container layers have been added. "
+                      "Performance may suffer.");
+    addedLayer = true;
 
-    if (subdocRootFrame && parentAPD != subdocAPD) {
-      NS_WARN_IF_FALSE(!addedLayer,
-                       "Two container layers have been added. "
-                       "Performance may suffer.");
-      addedLayer = true;
+    nsDisplayZoom* zoomItem =
+      new (aBuilder) nsDisplayZoom(aBuilder, subdocRootFrame, &childItems,
+                                   subdocAPD, parentAPD);
+    childItems.AppendToTop(zoomItem);
+  }
 
-      nsDisplayZoom* zoomItem =
-        new (aBuilder) nsDisplayZoom(aBuilder, subdocRootFrame, &childItems,
-                                     subdocAPD, parentAPD);
-      childItems.AppendToTop(zoomItem);
-    }
-    
-    if (!addedLayer && presContext->IsRootContentDocument()) {
-      // We always want top level content documents to be in their own layer.
-      nsDisplayOwnLayer* layerItem = new (aBuilder) nsDisplayOwnLayer(
-        aBuilder, subdocRootFrame ? subdocRootFrame : this, &childItems);
-      childItems.AppendToTop(layerItem);
-    }
+  if (!addedLayer && presContext->IsRootContentDocument()) {
+    // We always want top level content documents to be in their own layer.
+    nsDisplayOwnLayer* layerItem = new (aBuilder) nsDisplayOwnLayer(
+      aBuilder, subdocRootFrame ? subdocRootFrame : this, &childItems);
+    childItems.AppendToTop(layerItem);
+  }
 
-    if (ShouldClipSubdocument()) {
-      nsDisplayClip* item =
-        new (aBuilder) nsDisplayClip(aBuilder, this, &childItems,
-                                     subdocBoundsInParentUnits);
-      // Clip children to the child root frame's rectangle
-      childItems.AppendToTop(item);
-    }
+  if (ShouldClipSubdocument()) {
+    nsDisplayClip* item =
+      new (aBuilder) nsDisplayClip(aBuilder, this, &childItems,
+                                   subdocBoundsInParentUnits);
+    // Clip children to the child root frame's rectangle
+    childItems.AppendToTop(item);
+  }
 
-    if (mIsInline) {
-      WrapReplacedContentForBorderRadius(aBuilder, &childItems, aLists);
-    } else {
-      aLists.Content()->AppendToTop(&childItems);
-    }
+  if (mIsInline) {
+    WrapReplacedContentForBorderRadius(aBuilder, &childItems, aLists);
+  } else {
+    aLists.Content()->AppendToTop(&childItems);
   }
 
   // delete childItems in case of OOM