Read EDID for the 1st display for startup

ui/ozone/common/display_util.h

 // Copyright 2014 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 UI_OZONE_COMMON_DISPLAY_UTIL_H_
 #define UI_OZONE_COMMON_DISPLAY_UTIL_H_
 
+#include <vector>
+
 #include "ui/ozone/common/gpu/ozone_gpu_message_params.h"
 
+namespace base {
+class FilePath;
+}
+
 namespace ui {
 
 class DisplayMode;
 class DisplaySnapshot;
 
 // Conforms to the std::UnaryPredicate interface such that it can be used to
 // find a display with |display_id| in std:: containers (ie: std::vector).
 class FindDisplayById {
  public:
   FindDisplayById(int64_t display_id);
 
   bool operator()(const DisplaySnapshot_Params& display) const;
 
  private:
   int64_t display_id_;
 };
 
 DisplayMode_Params GetDisplayModeParams(const DisplayMode& mode);
 DisplaySnapshot_Params GetDisplaySnapshotParams(const DisplaySnapshot& display);
 
 // Create a display using the Ozone command line parameters.
-DisplaySnapshot_Params CreateSnapshotFromCommandLine();
+// Return false if the command line flags are not specified.
+bool CreateSnapshotFromCommandLine(DisplaySnapshot_Params* snapshot_out);
+
+// Create a display snapshot from |file| that contains EDID.
+// Return false if the file doesn't exist, or it doesn't contain valid EDID.
+bool CreateSnapshotFromEDIDFile(const base::FilePath& file,
+                                DisplaySnapshot_Params* snapshot_out);
+
+// Create a display snaphot from edid.
+// Return false if it doesn't contain valid EDID.
+bool CreateSnapshotFromEDID(bool internal,
+                            const std::vector<uint8_t>& edid,
+                            DisplaySnapshot_Params* snapshot_out);
 
 }  // namespace ui
 
 #endif  // UI_OZONE_COMMON_DISPLAY_UTIL_H_