make sure to re-initialize SurfaceTexture to its default state on disconnect

this caused problems where the NavigationBar would disapear or be
drawn in the wrong orientation.

Change-Id: I083c41338db83a4afd14f427caec2f31c180d734
diff --git a/libs/gui/SurfaceTextureClient.cpp b/libs/gui/SurfaceTextureClient.cpp
index 5a35b4d..710ef94 100644
--- a/libs/gui/SurfaceTextureClient.cpp
+++ b/libs/gui/SurfaceTextureClient.cpp
@@ -407,8 +407,15 @@
     LOGV("SurfaceTextureClient::disconnect");
     Mutex::Autolock lock(mMutex);
     int err = mSurfaceTexture->disconnect(api);
-    if (!err && api == NATIVE_WINDOW_API_CPU) {
-        mConnectedToCpu = false;
+    if (!err) {
+        freeAllBuffers();
+        mReqFormat = 0;
+        mReqWidth = 0;
+        mReqHeight = 0;
+        mReqUsage = 0;
+        if (api == NATIVE_WINDOW_API_CPU) {
+            mConnectedToCpu = false;
+        }
     }
     return err;
 }