Add CachingHint into SurfaceFlinger

Some system layers may need to be excluded from surfaceflinger caching
for a variety of reasons, including power or image quality
considerations. This provides a mechanism for those system layers to
never be cached on the GPU.

Bug: 259311918
Test: libcompositionengine_test
Test: run test app and inspect planner state
Change-Id: I35418ad5a41cb2546e3b27b0af290bf3c31a0180
diff --git a/libs/gui/SurfaceComposerClient.cpp b/libs/gui/SurfaceComposerClient.cpp
index c508917..001d475 100644
--- a/libs/gui/SurfaceComposerClient.cpp
+++ b/libs/gui/SurfaceComposerClient.cpp
@@ -1729,6 +1729,20 @@
     return *this;
 }
 
+SurfaceComposerClient::Transaction& SurfaceComposerClient::Transaction::setCachingHint(
+        const sp<SurfaceControl>& sc, gui::CachingHint cachingHint) {
+    layer_state_t* s = getLayerState(sc);
+    if (!s) {
+        mStatus = BAD_INDEX;
+        return *this;
+    }
+    s->what |= layer_state_t::eCachingHintChanged;
+    s->cachingHint = cachingHint;
+
+    registerSurfaceControlForCallback(sc);
+    return *this;
+}
+
 SurfaceComposerClient::Transaction& SurfaceComposerClient::Transaction::setHdrMetadata(
         const sp<SurfaceControl>& sc, const HdrMetadata& hdrMetadata) {
     layer_state_t* s = getLayerState(sc);