Add GN split_list function

tools/gn/functions.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef TOOLS_GN_FUNCTIONS_H_
 #define TOOLS_GN_FUNCTIONS_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 287 matching lines @@
 
 extern const char kSourceSet[];
 extern const char kSourceSet_HelpShort[];
 extern const char kSourceSet_Help[];
 Value RunSourceSet(Scope* scope,
                    const FunctionCallNode* function,
                    const std::vector<Value>& args,
                    BlockNode* block,
                    Err* err);
 
+extern const char kSplitList[];
+extern const char kSplitList_HelpShort[];
+extern const char kSplitList_Help[];
+Value RunSplitList(Scope* scope,
+                   const FunctionCallNode* function,
+                   const ListNode* args_list,
+                   Err* err);
+
 extern const char kStaticLibrary[];
 extern const char kStaticLibrary_HelpShort[];
 extern const char kStaticLibrary_Help[];
 Value RunStaticLibrary(Scope* scope,
                        const FunctionCallNode* function,
                        const std::vector<Value>& args,
                        BlockNode* block,
                        Err* err);
 
 extern const char kTarget[];
@@ skipping 169 matching lines @@
   Scope* scope_;
   const FunctionCallNode* function_;
   const char* type_description_;
 
   // Set to true when the key is added to the scope so we don't try to
   // delete nonexistant keys which will cause assertions.
   bool key_added_;
 };
 
 #endif  // TOOLS_GN_FUNCTIONS_H_