NaCl SDK: Remove some unused variables in input_event.cc example

native_client_sdk/src/examples/api/input_event/input_event.cc

Index: native_client_sdk/src/examples/api/input_event/input_event.cc
diff --git a/native_client_sdk/src/examples/api/input_event/input_event.cc b/native_client_sdk/src/examples/api/input_event/input_event.cc
index fee260bf74c53681596e96bf6fe3415b1bea7717..583c230091755670a95f058b38acbc067fa2271f 100644
--- a/native_client_sdk/src/examples/api/input_event/input_event.cc
+++ b/native_client_sdk/src/examples/api/input_event/input_event.cc
@@ -24,10 +24,6 @@
 
 namespace {
 
-const char* const kDidChangeFocus = "DidChangeFocus";
-const char* const kHaveFocus = "HaveFocus";
-const char* const kDontHaveFocus = "DontHaveFocus";
-
 std::string ModifierToString(uint32_t modifier) {
   std::string s;
   if (modifier & PP_INPUTEVENT_MODIFIER_SHIFTKEY) {