Fix/suppress google-explicit-constructor warnings

* Add explicit to conversion constructors/operators

Bug: 28341362
Test: make with WITH_TIDY=1 DEFAULT_GLOBAL_TIDY_CHECKS=-*,google-explicit-constructor
Change-Id: Iac8f3aa14cd04861f6bcbab56b0dfc28c9a89e53
diff --git a/include/input/Input.h b/include/input/Input.h
index cfcafab..756b337 100644
--- a/include/input/Input.h
+++ b/include/input/Input.h
@@ -661,7 +661,7 @@
  */
 class PooledInputEventFactory : public InputEventFactoryInterface {
 public:
-    PooledInputEventFactory(size_t maxPoolSize = 20);
+    explicit PooledInputEventFactory(size_t maxPoolSize = 20);
     virtual ~PooledInputEventFactory();
 
     virtual KeyEvent* createKeyEvent();
diff --git a/include/input/KeyCharacterMap.h b/include/input/KeyCharacterMap.h
index 33d2757..5e542b8 100644
--- a/include/input/KeyCharacterMap.h
+++ b/include/input/KeyCharacterMap.h
@@ -196,7 +196,7 @@
         };
 
         struct Property {
-            inline Property(int32_t property = 0, int32_t metaState = 0) :
+            inline explicit Property(int32_t property = 0, int32_t metaState = 0) :
                     property(property), metaState(metaState) { }
 
             int32_t property;
diff --git a/libs/input/tests/TestHelpers.h b/libs/input/tests/TestHelpers.h
index fe87bb9..343d81f 100644
--- a/libs/input/tests/TestHelpers.h
+++ b/libs/input/tests/TestHelpers.h
@@ -62,7 +62,7 @@
     int mDelayMillis;
 
 public:
-    DelayedTask(int delayMillis) : mDelayMillis(delayMillis) { }
+    explicit DelayedTask(int delayMillis) : mDelayMillis(delayMillis) { }
 
 protected:
     virtual ~DelayedTask() { }