Remove redundant cmake::GetIsPropertyDefined method

We already have cmake::IsPropertyDefined for the same reason.

Source/cmTarget.cxx

@@ -6823,7 +6823,7 @@ void checkPropertyConsistency(cmTarget *depender, cmTarget *dependee,
       pi != props.end(); ++pi)
     {
     if (depender->GetMakefile()->GetCMakeInstance()
-                      ->GetIsPropertyDefined(pi->c_str(),
+                      ->IsPropertyDefined(pi->c_str(),
                                               cmProperty::TARGET))
       {
       cmOStringStream e;

Source/cmake.cxx

@@ -3640,13 +3640,6 @@ void cmake::DefineProperty(const char *name, cmProperty::ScopeType scope,
                                                   chained);
 }
 
-bool cmake::GetIsPropertyDefined(const char *name,
-                                 cmProperty::ScopeType scope)
-{
-  return this->PropertyDefinitions[scope].find(name) !=
-                                      this->PropertyDefinitions[scope].end();
-}
-
 cmPropertyDefinition *cmake
 ::GetPropertyDefinition(const char *name,
                         cmProperty::ScopeType scope)

Source/cmake.h

@@ -349,8 +349,6 @@ class cmake
                       bool chain = false,
                       const char *variableGroup = 0);
 
-  bool GetIsPropertyDefined(const char *name, cmProperty::ScopeType scope);
-
   // get property definition
   cmPropertyDefinition *GetPropertyDefinition
   (const char *name, cmProperty::ScopeType scope);