Fix some problems reported by clang static analyzer

Source/core/rendering/RenderLayer.cpp

Index: Source/core/rendering/RenderLayer.cpp
diff --git a/Source/core/rendering/RenderLayer.cpp b/Source/core/rendering/RenderLayer.cpp
index 0eef2763bebe2734f6a1a5304ccb42bf5c01374b..4f2a04d3771dcffdae5a4ff0c4ad01c55b54e171 100644
--- a/Source/core/rendering/RenderLayer.cpp
+++ b/Source/core/rendering/RenderLayer.cpp
@@ -2073,10 +2073,8 @@ void RenderLayer::paintLayerContents(GraphicsContext* context, const LayerPainti
         LayoutRect filterRepaintRect = filterInfo->dirtySourceRect();
         filterRepaintRect.move(offsetFromRoot.x(), offsetFromRoot.y());
 
-        if (!rootRelativeBoundsComputed) {
+        if (!rootRelativeBoundsComputed)
             rootRelativeBounds = calculateLayerBounds(paintingInfo.rootLayer, &offsetFromRoot, 0);
-            rootRelativeBoundsComputed = true;
-        }
 
         if (filterPainter.prepareFilterEffect(this, rootRelativeBounds, paintingInfo.paintDirtyRect, filterRepaintRect)) {
             // Now we know for sure, that the source image will be updated, so we can revert our tracking repaint rect back to zero.