BQ: Modify consumer buffer count interfaces

- Rename setDefaultMaxBufferCount() to setMaxBufferCount(). Modify it
  to be hard maximum on the number of buffers that can't be overwritten
  by the producer.
- Enforce the maximum buffer count in setMaxAcquiredBufferCount(),
  setMaxDequeuedBufferCount(), and setAsyncMode().
- Remove mOverrideMaxBufferCount as it's no longer needed since
  overriding is no longer possible.
- Expose setMaxAcquiredBufferCount() in GLConsumer.
- Remove disableAsyncBuffer(), it was only being used for single buffer
  mode. Single buffer mode is now achievable with setMaxBufferCount().

Bug 13174928

Change-Id: Ia33799f42751272a711fbd8559f7602ce9f18e4f
diff --git a/cmds/flatland/GLHelper.cpp b/cmds/flatland/GLHelper.cpp
index 3155766..ddf3aa8 100644
--- a/cmds/flatland/GLHelper.cpp
+++ b/cmds/flatland/GLHelper.cpp
@@ -207,7 +207,7 @@
     sp<GLConsumer> glc = new GLConsumer(consumer, name,
             GL_TEXTURE_EXTERNAL_OES, false, true);
     glc->setDefaultBufferSize(w, h);
-    glc->setDefaultMaxBufferCount(3);
+    producer->setMaxDequeuedBufferCount(2);
     glc->setConsumerUsageBits(GRALLOC_USAGE_HW_COMPOSER);
 
     sp<ANativeWindow> anw = new Surface(producer);