camera: maintain autolock invariant

b/7090644

Fix lock invariant for mStopCallbackLock expected by Mutex::Autolock.

Change-Id: Ifc4e77dea7d7deb5bbdfe544379dd40ded680831
Signed-off-by: Iliyan Malchev <malchev@google.com>
diff --git a/camera/QCameraHWI_Preview.cpp b/camera/QCameraHWI_Preview.cpp
index 866f1f7..b83f2eb 100644
--- a/camera/QCameraHWI_Preview.cpp
+++ b/camera/QCameraHWI_Preview.cpp
@@ -1015,6 +1015,7 @@
             pcb(msgType, data, 0, metadata, mHalCamCtrl->mCallbackCookie);
           if (previewMem)
               previewMem->release(previewMem);
+          mStopCallbackLock.lock();
       }
 	  ALOGV("end of cb");
   } else {
@@ -1035,6 +1036,7 @@
               rcb(timeStamp, CAMERA_MSG_VIDEO_FRAME,
                       mHalCamCtrl->mRecordingMemory.metadata_memory[frame->def.idx],
                       0, mHalCamCtrl->mCallbackCookie);
+              mStopCallbackLock.lock();
           }else
               flagwait = 0;
       }
@@ -1044,6 +1046,7 @@
               rcb(timeStamp, CAMERA_MSG_VIDEO_FRAME,
                       mHalCamCtrl->mPreviewMemory.camera_memory[frame->def.idx],
                       0, mHalCamCtrl->mCallbackCookie);
+              mStopCallbackLock.lock();
       }
 
       if(flagwait){
@@ -1167,6 +1170,7 @@
             pcb(msgType, data, 0, metadata, mHalCamCtrl->mCallbackCookie);
           if (previewMem)
               previewMem->release(previewMem);
+          mStopCallbackLock.lock();
       }
 
       if(MM_CAMERA_OK != cam_evt_buf_done(mCameraId, &mNotifyBuffer[frame->def.idx])) {