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/device1/CameraHardwareInterface.h b/services/camera/libcameraservice/device1/CameraHardwareInterface.h
index 0b883ba..952bae1 100644
--- a/services/camera/libcameraservice/device1/CameraHardwareInterface.h
+++ b/services/camera/libcameraservice/device1/CameraHardwareInterface.h
@@ -73,7 +73,7 @@
 
 class CameraHardwareInterface : public virtual RefBase {
 public:
-    CameraHardwareInterface(const char *name):
+    explicit CameraHardwareInterface(const char *name):
             mDevice(nullptr),
             mName(name),
             mPreviewScalingMode(NOT_SET),
@@ -543,9 +543,9 @@
             commonInitialization();
         }
 
-        CameraHeapMemory(size_t buf_size, uint_t num_buffers = 1) :
-                         mBufSize(buf_size),
-                         mNumBufs(num_buffers)
+        explicit CameraHeapMemory(size_t buf_size, uint_t num_buffers = 1) :
+                                  mBufSize(buf_size),
+                                  mNumBufs(num_buffers)
         {
             mHeap = new MemoryHeapBase(buf_size * num_buffers);
             commonInitialization();