QCamera2: fix a bug in stateMachine

In previewPicTaking state, when start_recording is called, it
should call startRecording() instead of stopRecording().

Change-Id: I3f2d31ed3c99fe275f74efe720547a38f9920853
diff --git a/QCamera2/HAL/QCameraStateMachine.cpp b/QCamera2/HAL/QCameraStateMachine.cpp
index 42fe32e..3ab835f 100644
--- a/QCamera2/HAL/QCameraStateMachine.cpp
+++ b/QCamera2/HAL/QCameraStateMachine.cpp
@@ -2458,9 +2458,15 @@
         break;
     case QCAMERA_SM_EVT_START_RECORDING:
         {
-            rc = m_parent->stopRecording();
-            if (rc == NO_ERROR) {
-                m_state = QCAMERA_SM_STATE_VIDEO_PIC_TAKING;
+            if (m_parent->isZSLMode()) {
+                ALOGE("%s: cannot handle evt(%d) in state(%d) in ZSL mode",
+                      __func__, evt, m_state);
+                rc = INVALID_OPERATION;
+            } else {
+                rc = m_parent->startRecording();
+                if (rc == NO_ERROR) {
+                    m_state = QCAMERA_SM_STATE_VIDEO_PIC_TAKING;
+                }
             }
             result.status = rc;
             result.request_api = evt;