SurfaceFlinger: Fix PTS on stale buffers

SurfaceFlinger's (Layer's) shadow copy of the BufferQueue queue was
getting out of sync for a few reasons. This change fixes these by
doing the following:

- Adds a check to re-synchronize the shadow copy every time we
  successfully acquire a buffer by first dropping stale buffers before
  removing the current buffer.
- Avoids trying to perform updates for buffers which have been rejected
  (for incorrect dimensions) by SurfaceFlinger.
- Adds IGraphicBufferConsumer::setShadowQueueSize, which allows the
  consumer to notify the BufferQueue that it is maintaining a shadow
  copy of the queue and prevents it from dropping so many buffers
  during acquireBuffer that it ends up returning a buffer for which the
  consumer has not yet received an onFrameAvailable call.

Bug: 20096136
Change-Id: I78d0738428005fc19b3be85cc8f1db498043612f
(cherry picked from commit 2e36f2283f48ab764b496490c73a132acf21df3a)
diff --git a/libs/gui/IGraphicBufferConsumer.cpp b/libs/gui/IGraphicBufferConsumer.cpp
index 6658ab1..480dfb6 100644
--- a/libs/gui/IGraphicBufferConsumer.cpp
+++ b/libs/gui/IGraphicBufferConsumer.cpp
@@ -52,6 +52,7 @@
     SET_CONSUMER_USAGE_BITS,
     SET_TRANSFORM_HINT,
     GET_SIDEBAND_STREAM,
+    SET_SHADOW_QUEUE_SIZE,
     DUMP,
 };
 
@@ -269,6 +270,17 @@
         return stream;
     }
 
+    virtual void setShadowQueueSize(size_t size) {
+        Parcel data, reply;
+        data.writeInterfaceToken(IGraphicBufferConsumer::getInterfaceDescriptor());
+        data.writeInt64(static_cast<int64_t>(size));
+        status_t result = remote()->transact(SET_SHADOW_QUEUE_SIZE, data, &reply);
+        if (result != NO_ERROR) {
+            ALOGE("setShadowQueueSize failed (%d)", result);
+            return;
+        }
+    }
+
     virtual void dump(String8& result, const char* prefix) const {
         Parcel data, reply;
         data.writeInterfaceToken(IGraphicBufferConsumer::getInterfaceDescriptor());
@@ -423,6 +435,12 @@
             }
             return NO_ERROR;
         }
+        case SET_SHADOW_QUEUE_SIZE: {
+            CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
+            size_t size = static_cast<size_t>(data.readInt64());
+            setShadowQueueSize(size);
+            return NO_ERROR;
+        }
         case DUMP: {
             CHECK_INTERFACE(IGraphicBufferConsumer, data, reply);
             String8 result = data.readString8();