Add plumbing for sending stretch effect to SF

Bug: 179047472
Test: builds & boots, doesn't do anything yet
Change-Id: Ib8cccdde518f0591c2f2ee3416684442f37a1e06
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index df14003..1fe0e26 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -488,6 +488,7 @@
     compositionState->alpha = alpha;
     compositionState->backgroundBlurRadius = drawingState.backgroundBlurRadius;
     compositionState->blurRegions = drawingState.blurRegions;
+    compositionState->stretchEffect = drawingState.stretchEffect;
 }
 
 void Layer::prepareGeometryCompositionState() {
@@ -556,8 +557,8 @@
             isOpaque(drawingState) && !usesRoundedCorners && getAlpha() == 1.0_hf;
 
     // Force client composition for special cases known only to the front-end.
-    if (isHdrY410() || usesRoundedCorners || drawShadows() ||
-        getDrawingState().blurRegions.size() > 0) {
+    if (isHdrY410() || usesRoundedCorners || drawShadows() || drawingState.blurRegions.size() > 0 ||
+        drawingState.stretchEffect.hasEffect()) {
         compositionState->forceClientComposition = true;
     }
 }
@@ -656,6 +657,7 @@
         layerSettings.backgroundBlurRadius = getBackgroundBlurRadius();
         layerSettings.blurRegions = getBlurRegions();
     }
+    layerSettings.stretchEffect = getDrawingState().stretchEffect;
     // Record the name of the layer for debugging further down the stack.
     layerSettings.name = getName();
     return layerSettings;
@@ -1423,6 +1425,19 @@
     return true;
 }
 
+bool Layer::setStretchEffect(const StretchEffect& effect) {
+    StretchEffect temp = effect;
+    temp.sanitize();
+    if (mCurrentState.stretchEffect == temp) {
+        return false;
+    }
+    mCurrentState.sequence++;
+    mCurrentState.stretchEffect = temp;
+    mCurrentState.modified = true;
+    setTransactionFlags(eTransactionNeeded);
+    return true;
+}
+
 void Layer::updateTreeHasFrameRateVote() {
     const auto traverseTree = [&](const LayerVector::Visitor& visitor) {
         auto parent = getParent();