Remove CanChallengePlatform() and CheckPlatformState().

ppapi/cpp/private/platform_verification.cc

Index: ppapi/cpp/private/platform_verification.cc
diff --git a/ppapi/cpp/private/platform_verification.cc b/ppapi/cpp/private/platform_verification.cc
index f90857006963cd83eaf5fb6c07262a129baae388..720c9109d9ff7074e850387e0ee3b4d7151837ca 100644
--- a/ppapi/cpp/private/platform_verification.cc
+++ b/ppapi/cpp/private/platform_verification.cc
@@ -36,15 +36,6 @@ PlatformVerification::PlatformVerification(const InstanceHandle& instance) {
 
 PlatformVerification::~PlatformVerification() {}
 
-int32_t PlatformVerification::CanChallengePlatform(
-    const CompletionCallbackWithOutput<bool>& callback) {
-  if (!HasInterface())
-    return callback.MayForce(PP_ERROR_NOINTERFACE);
-
-  return GetInterface()->CanChallengePlatform(
-      pp_resource(), callback.output(), callback.pp_completion_callback());
-}
-
 int32_t PlatformVerification::ChallengePlatform(
     const Var& service_id,
     const Var& challenge,