Camera2: Move still capture processing to separate thread.

To avoid stalling HAL when it queues up new buffers for still capture,
process still captures in a separate thread. Also move Camera2Heap to
its own class so it can be used by the CaptureProcessor.

Bug: 6243944
Change-Id: Id38e2a52367c0985812fcd4fd9af3ef90beef43f
diff --git a/services/camera/libcameraservice/Android.mk b/services/camera/libcameraservice/Android.mk
index eac6163..9898a70 100644
--- a/services/camera/libcameraservice/Android.mk
+++ b/services/camera/libcameraservice/Android.mk
@@ -13,7 +13,8 @@
     Camera2Device.cpp \
     camera2/CameraMetadata.cpp \
     camera2/Parameters.cpp \
-    camera2/FrameProcessor.cpp
+    camera2/FrameProcessor.cpp \
+    camera2/CaptureProcessor.cpp
 
 LOCAL_SHARED_LIBRARIES:= \
     libui \