Fix google-explicit-constructor warnings.

Bug: 28341362
Change-Id: I625fbab25f16282c2ea929cd16283d9d146fa17b
diff --git a/media/libmedia/IRemoteDisplay.cpp b/media/libmedia/IRemoteDisplay.cpp
index 869d11a..85c7bd6 100644
--- a/media/libmedia/IRemoteDisplay.cpp
+++ b/media/libmedia/IRemoteDisplay.cpp
@@ -30,7 +30,7 @@
 class BpRemoteDisplay: public BpInterface<IRemoteDisplay>
 {
 public:
-    BpRemoteDisplay(const sp<IBinder>& impl)
+    explicit BpRemoteDisplay(const sp<IBinder>& impl)
         : BpInterface<IRemoteDisplay>(impl)
     {
     }