Move inval dedup to Window for wider usages.

tools/viewer/sk_app/android/surface_glue_android.cpp

Index: tools/viewer/sk_app/android/surface_glue_android.cpp
diff --git a/tools/viewer/sk_app/android/surface_glue_android.cpp b/tools/viewer/sk_app/android/surface_glue_android.cpp
index 3a4fca539c8204489e381c4b6cba7c0fc0c261c6..06701902c4247a425efa87a8ddb01b12ee682eab 100644
--- a/tools/viewer/sk_app/android/surface_glue_android.cpp
+++ b/tools/viewer/sk_app/android/surface_glue_android.cpp
@@ -71,8 +71,12 @@ void SkiaAndroidApp::setTitle(const char* title) const {
 }
 
 void SkiaAndroidApp::paintIfNeeded() {
-    if (fNativeWindow && fWindow) {
-        fWindow->onPaint();
+    if (fWindow) {
+        if (fNativeWindow) {
+            fWindow->onPaint();
+        } else {
+            fWindow->uncheckInval();
+        }
     }
 }
 
@@ -86,14 +90,6 @@ void SkiaAndroidApp::readMessage(Message* message) const {
     SkASSERT(readSize == sizeof(Message));
 }
 
-void SkiaAndroidApp::inval() {
-    SkAutoMutexAcquire ama(fMutex);
-    if (!fIsContentInvalidated) {
-        postMessage(Message(kContentInvalidated));
-        fIsContentInvalidated = true;
-    }
-}
-
 int SkiaAndroidApp::message_callback(int fd, int events, void* data) {
     auto skiaAndroidApp = (SkiaAndroidApp*)data;
     Message message;
@@ -108,8 +104,6 @@ int SkiaAndroidApp::message_callback(int fd, int events, void* data) {
             return 0;
         }
         case kContentInvalidated: {
-            SkAutoMutexAcquire ama(skiaAndroidApp->fMutex);
-            skiaAndroidApp->fIsContentInvalidated = false;
             skiaAndroidApp->paintIfNeeded();
             break;
         }