Merge "Avoid saveLayer in RippleDrawable if the background won't draw" into lmp-mr1-dev

        final ChildDrawable[] array = mLayerState.mChildren;

        final int count = mLayerState.mNum;

        // We don't need a layer if we don't expect to draw any ripples, we have

        // an explicit mask, or if the non-mask content is all opaque.

        // We don't need a layer if we don't expect to draw any ripples or

        // a background, we have an explicit mask, or if the non-mask content

        // is all opaque.

        boolean needsLayer = false;

        if ((mExitingRipplesCount > 0 || mBackground != null) && mMask == null) {

        if ((mExitingRipplesCount > 0 || (mBackground != null && mBackground.shouldDraw()))

                && mMask == null) {

            for (int i = 0; i < count; i++) {

                if (array[i].mId != R.id.mask

                        && array[i].mDrawable.getOpacity() != PixelFormat.OPAQUE) {