Delete RenderProxy off of the cleaner thread

Speculation for the cause of an ANR. HardwareRenderer's
cleaner can block on RenderThread, which in turn blocks ART's
cleaner thread. This can potentially cause other blockages, but
it's also poor behavior to have such a long-running Cleaner anyway.

Avoid this by putting cleanup to CommonPool.

Bug: 191514384
Test: make, CtsUiRenderingTestCases still passes

Change-Id: I8190f7862528c3ac39ce636f6fca229322480968

libs/hwui/jni/android_graphics_HardwareRenderer.cpp

@@ -247,7 +247,7 @@ static jlong android_view_ThreadedRenderer_createProxy(JNIEnv* env, jobject claz
 static void android_view_ThreadedRenderer_deleteProxy(JNIEnv* env, jobject clazz,
         jlong proxyPtr) {
     RenderProxy* proxy = reinterpret_cast<RenderProxy*>(proxyPtr);
-    delete proxy;
+    RenderProxy::asyncDelete(proxy);
 }
 
 static jboolean android_view_ThreadedRenderer_loadSystemProperties(JNIEnv* env, jobject clazz,

libs/hwui/renderthread/RenderProxy.cpp

@@ -26,6 +26,7 @@
 #include "renderthread/CanvasContext.h"
 #include "renderthread/RenderTask.h"
 #include "renderthread/RenderThread.h"
+#include "thread/CommonPool.h"
 #include "utils/Macros.h"
 #include "utils/TimeUtils.h"
 
@@ -42,6 +43,17 @@ RenderProxy::RenderProxy(bool translucent, RenderNode* rootRenderNode,
     mDrawFrameTask.setContext(&mRenderThread, mContext, rootRenderNode);
 }
 
+void RenderProxy::asyncDelete(RenderProxy* proxy) {
+    if (!proxy) return;
+
+    if (proxy->mContext) {
+        // Use the common pool because ~RenderProxy blocks on calling into RenderThread
+        CommonPool::post([proxy]() { delete proxy; });
+    } else {
+        delete proxy;
+    }
+}
+
 RenderProxy::~RenderProxy() {
     destroyContext();
 }

libs/hwui/renderthread/RenderProxy.h

@@ -62,10 +62,14 @@ enum {
  * references RenderProxy fields. This is safe as RenderProxy cannot
  * be deleted if it is blocked inside a call.
  */
-class RenderProxy {
+class RenderProxy final {
 public:
     RenderProxy(bool opaque, RenderNode* rootNode, IContextFactory* contextFactory);
-    virtual ~RenderProxy();
+    ~RenderProxy();
+
+    // Schedules a delete of the RenderProxy at a later date. Avoids blocking the current thread
+    // on destruction which ~RenderProxy does by default.
+    static void asyncDelete(RenderProxy*);
 
     // Won't take effect until next EGLSurface creation
     void setSwapBehavior(SwapBehavior swapBehavior);