Add option to gen_snapshot for creating a Makefile describing a snapshot's dependencies.

runtime/bin/loader.h

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_BIN_LOADER_H_
 #define RUNTIME_BIN_LOADER_H_
 
 #include "bin/isolate_data.h"
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
@@ skipping 11 matching lines @@
 
   static void InitForSnapshot(const char* snapshot_uri);
 
   static Dart_Handle ReloadNativeExtensions();
 
   // Loads contents of the specified url.
   static Dart_Handle LoadUrlContents(Dart_Handle url,
                                      uint8_t** payload,
                                      intptr_t* payload_length);
 
+  static Dart_Handle ResolveAsFilePath(Dart_Handle url,
+                                       uint8_t** payload,
+                                       intptr_t* payload_length);
 
   // A static tag handler that hides all usage of a loader for an isolate.
   static Dart_Handle LibraryTagHandler(Dart_LibraryTag tag,
                                        Dart_Handle library,
                                        Dart_Handle url);
 
   Dart_Handle error() const { return error_; }
 
   static void InitOnce();
 
@@ skipping 57 matching lines @@
   /// Queue |message| and notify the loader that a message is available.
   void QueueMessage(Dart_CObject* message);
 
   /// Blocks the caller until the loader is finished.
   void BlockUntilComplete(ProcessResult process_result);
 
   /// Returns false if |result| is an error and the loader should quit.
   static bool ProcessResultLocked(Loader* loader, IOResult* result);
 
   /// Returns false if |result| is an error and the loader should quit.
-  static bool ProcessUrlLoadResultLocked(Loader* loader, IOResult* result);
+  static bool ProcessPayloadResultLocked(Loader* loader, IOResult* result);
 
   /// Returns false if an error occurred and the loader should quit.
   bool ProcessQueueLocked(ProcessResult process_result);
 
   // Special inner tag handler for dart: uris.
   static Dart_Handle DartColonLibraryTagHandler(Dart_LibraryTag tag,
                                                 Dart_Handle library,
                                                 Dart_Handle url,
                                                 const char* library_url_string,
                                                 const char* url_string);
@@ skipping 22 matching lines @@
 
   // This is the global callback for the native message handlers.
   static void NativeMessageHandler(Dart_Port dest_port_id,
                                    Dart_CObject* message);
 };
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // RUNTIME_BIN_LOADER_H_