Camera: some patchs for offline processing

Test: CTS OfflineSessionTest
Bug: 135142453

Change-Id: I09a19b3b2e366855ed35b588f75f9734f505072c
diff --git a/services/camera/libcameraservice/device3/Camera3OfflineSession.cpp b/services/camera/libcameraservice/device3/Camera3OfflineSession.cpp
index 8150de3..f95eb16 100644
--- a/services/camera/libcameraservice/device3/Camera3OfflineSession.cpp
+++ b/services/camera/libcameraservice/device3/Camera3OfflineSession.cpp
@@ -167,7 +167,9 @@
         streams.push_back(mInputStream);
     }
 
-    mSession->close();
+    if (mSession != nullptr) {
+        mSession->close();
+    }
 
     FlushInflightReqStates states {
         mId, mOfflineReqsLock, mOfflineReqs, mUseHalBufManager,