Fix HardwareRenderers becoming invalidated by TRIM

Fixes: 335646931
Test: repro steps in bug
Change-Id: I6b22d202b71effa1a7136a20f51b38732d0fde74

1 files changed, 9 insertions, 1 deletions

diff --git a/libs/hwui/renderthread/CanvasContext.cpp b/libs/hwui/renderthread/CanvasContext.cpp
index 66e089627a7b..8bb11badb607 100644
--- a/libs/hwui/renderthread/CanvasContext.cpp
+++ b/libs/hwui/renderthread/CanvasContext.cpp
@@ -1010,7 +1010,15 @@ void CanvasContext::destroyHardwareResources() {
 }
 
 void CanvasContext::onContextDestroyed() {
-    destroyHardwareResources();
+    // We don't want to destroyHardwareResources as that will invalidate display lists which
+    // the client may not be expecting. Instead just purge all scratch resources
+    if (mRenderPipeline->isContextReady()) {
+        freePrefetchedLayers();
+        for (const sp<RenderNode>& node : mRenderNodes) {
+            node->destroyLayers();
+        }
+        mRenderPipeline->onDestroyHardwareResources();
+    }
 }
 
 DeferredLayerUpdater* CanvasContext::createTextureLayer() {