Camera: Add preview callback surface support

- Add call to set a preview callback surface
- Implement support for HAL2/3 devices
- Still need HAL1 implementation

Change-Id: I0dc0bd72e43d871aa487858d1665c1efca633ffe
diff --git a/services/camera/libcameraservice/CameraClient.cpp b/services/camera/libcameraservice/CameraClient.cpp
index e577fa3..be78f69 100644
--- a/services/camera/libcameraservice/CameraClient.cpp
+++ b/services/camera/libcameraservice/CameraClient.cpp
@@ -347,6 +347,12 @@
     }
 }
 
+status_t CameraClient::setPreviewCallbackTarget(
+        const sp<IGraphicBufferProducer>& callbackProducer) {
+    ALOGE("%s: Unimplemented!", __FUNCTION__);
+    return INVALID_OPERATION;
+}
+
 // start preview mode
 status_t CameraClient::startPreview() {
     LOG1("startPreview (pid %d)", getCallingPid());