Fix clang-tidy warnings in camera.

* Add explicit keyword to conversion constructors.
Bug: 28341362
* Use const reference type for read-only parameters.
Bug: 30407689
* Use const reference type to avoid unnecessary copy.
Bug: 30413862
Test: build with WITH_TIDY=1

Change-Id: I71d3008da843ba5f1df1a73a320fb2af6ceffa16
diff --git a/services/camera/libcameraservice/device3/StatusTracker.h b/services/camera/libcameraservice/device3/StatusTracker.h
index 49cecb3..3a1d85c 100644
--- a/services/camera/libcameraservice/device3/StatusTracker.h
+++ b/services/camera/libcameraservice/device3/StatusTracker.h
@@ -45,7 +45,7 @@
  */
 class StatusTracker: public Thread {
   public:
-    StatusTracker(wp<Camera3Device> parent);
+    explicit StatusTracker(wp<Camera3Device> parent);
     ~StatusTracker();
 
     // An always-invalid component ID