BufferQueue improvements and APIs changes

this is the first step of a series of improvements to
BufferQueue. A few things happen in this change:

- setSynchronousMode() goes away as well as the SynchronousModeAllowed flag
- BufferQueue now defaults to (what used to be) synchronous mode
- a new "controlled by app" flag is passed when creating consumers and producers
  those flags are used to put the BufferQueue in a mode where it
  will never block if both flags are set. This is achieved by:
  - returning an error from dequeueBuffer() if it would block
  - making sure a buffer is always available by replacing
    the previous buffer with the new one in queueBuffer()
    (note: this is similar to what asynchrnous mode used to be)

Note: in this change EGL's swap-interval 0 is broken; this will be
fixed in another change.

Change-Id: I691f9507d6e2e158287e3039f2a79a4d4434211d
diff --git a/include/gui/Surface.h b/include/gui/Surface.h
index c25847c..6f12e77 100644
--- a/include/gui/Surface.h
+++ b/include/gui/Surface.h
@@ -61,8 +61,11 @@
      * However, once a Surface is connected, it'll prevent other Surfaces
      * referring to the same IGraphicBufferProducer to become connected and
      * therefore prevent them to be used as actual producers of buffers.
+     *
+     * the controlledByApp flag indicates that this Surface (producer) is
+     * controlled by the application. This flag is used at connect time.
      */
-    Surface(const sp<IGraphicBufferProducer>& bufferProducer);
+    Surface(const sp<IGraphicBufferProducer>& bufferProducer, bool controlledByApp = false);
 
     /* getIGraphicBufferProducer() returns the IGraphicBufferProducer this
      * Surface was created with. Usually it's an error to use the
@@ -228,6 +231,10 @@
     // window. this is only a hint, actual transform may differ.
     uint32_t mTransformHint;
 
+    // mProducerControlledByApp whether this buffer producer is controlled
+    // by the application
+    bool mProducerControlledByApp;
+
     // mConsumerRunningBehind whether the consumer is running more than
     // one buffer behind the producer.
     mutable bool mConsumerRunningBehind;