Camera: Clean up warnings and set -Werror

- Also fix error logging template inconsistency
- Also add a few error handling cases into camera2 NDK
  to deal with previously-ignored error codes

Bug: 27149500
Change-Id: I8f1f4c72252dd48d652f24b595b642199f20c327
diff --git a/services/camera/libcameraservice/utils/CameraTraces.h b/services/camera/libcameraservice/utils/CameraTraces.h
index d10dbc9..13ca16d 100644
--- a/services/camera/libcameraservice/utils/CameraTraces.h
+++ b/services/camera/libcameraservice/utils/CameraTraces.h
@@ -24,7 +24,7 @@
 namespace android {
 namespace camera3 {
 
-class CameraTracesImpl;
+struct CameraTracesImpl;
 
 // Collect a list of the process's stack traces
 class CameraTraces {