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/CameraFlashlight.cpp b/services/camera/libcameraservice/CameraFlashlight.cpp
index ad08a68..6314ba5 100644
--- a/services/camera/libcameraservice/CameraFlashlight.cpp
+++ b/services/camera/libcameraservice/CameraFlashlight.cpp
@@ -812,7 +812,7 @@
 }
 
 status_t CameraHardwareInterfaceFlashControl::initializePreviewWindow(
-        sp<CameraHardwareInterface> device, int32_t width, int32_t height) {
+        const sp<CameraHardwareInterface>& device, int32_t width, int32_t height) {
     status_t res;
     BufferQueue::createBufferQueue(&mProducer, &mConsumer);