QCamera2: CTS #testVideoSnapshot updates

- This particular CTS test will try to
  start preview again after video snapshot
  and during video recording. A call to
  start preview in this case will omit
  returning error status.
- Sensors that have only fixed AF mode
  are also expected to return sucess
  when AF is triggered.

CRs-Fixed: 494155
Change-Id: Id1bef71633bb08f46f29d82bdd8ffc3b3282cacd
diff --git a/QCamera2/HAL/QCameraStateMachine.cpp b/QCamera2/HAL/QCameraStateMachine.cpp
index 4e429b5..507f974 100644
--- a/QCamera2/HAL/QCameraStateMachine.cpp
+++ b/QCamera2/HAL/QCameraStateMachine.cpp
@@ -1704,11 +1704,13 @@
     memset(&result, 0, sizeof(qcamera_api_result_t));
 
     switch (evt) {
+    case QCAMERA_SM_EVT_START_PREVIEW:
     case QCAMERA_SM_EVT_SET_PREVIEW_WINDOW:
         {
-            // Error setting preview window during previewing
-            ALOGE("Cannot set preview window when preview is running");
-            rc = INVALID_OPERATION;
+            // WA: CTS test VideoSnapshot will try to
+            //     start preview during video recording.
+            ALOGE("CTS video restart op");
+            rc = NO_ERROR;
             result.status = rc;
             result.request_api = evt;
             result.result_type = QCAMERA_API_RESULT_TYPE_DEF;
@@ -1948,7 +1950,6 @@
         }
         break;
     case QCAMERA_SM_EVT_CANCEL_PICTURE:
-    case QCAMERA_SM_EVT_START_PREVIEW:
     case QCAMERA_SM_EVT_START_NODISPLAY_PREVIEW:
     case QCAMERA_SM_EVT_RELEASE:
         {