Add support for virtual displays

ui/display/util/edid_parser.cc

 // 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.
 
 #include "ui/display/util/edid_parser.h"
 
 #include <algorithm>
 
 #include "base/hash.h"
 #include "base/strings/string_util.h"
 #include "base/sys_byteorder.h"
+#include "ui/display/util/display_util.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace ui {
 
 namespace {
 
-// Returns 64-bit persistent ID for the specified manufacturer's ID and
-// product_code_hash, and the index of the output it is connected to.
-// |output_index| is used to distinguish the displays of the same type. For
-// example, swapping two identical display between two outputs will not be
-// treated as swap. The 'serial number' field in EDID isn't used here because
-// it is not guaranteed to have unique number and it may have the same fixed
-// value (like 0).
-int64_t GetID(uint16_t manufacturer_id,
-              uint32_t product_code_hash,
-              uint8_t output_index) {
-  return ((static_cast<int64_t>(manufacturer_id) << 40) |
-          (static_cast<int64_t>(product_code_hash) << 8) | output_index);
-}
-
 // Returns a 32-bit identifier for this model of display, using
 // |manufacturer_id| and |product_code|.
 uint32_t GetProductID(uint16_t manufacturer_id, uint16_t product_code) {
   return ((static_cast<uint32_t>(manufacturer_id) << 16) |
           (static_cast<uint32_t>(product_code)));
 }
 
 }  // namespace
 
 bool GetDisplayIdFromEDID(const std::vector<uint8_t>& edid,
                           uint8_t output_index,
                           int64_t* display_id_out,
                           int64_t* product_id_out) {
   uint16_t manufacturer_id = 0;
   uint16_t product_code = 0;
   std::string product_name;
 
   // ParseOutputDeviceData fails if it doesn't have product_name.
   ParseOutputDeviceData(edid, &manufacturer_id, &product_code, &product_name,
                         nullptr, nullptr);
 
   if (manufacturer_id != 0) {
     // Generates product specific value from product_name instead of product
     // code.
     // See crbug.com/240341
     uint32_t product_code_hash =
         product_name.empty() ? 0 : base::Hash(product_name);
     // An ID based on display's index will be assigned later if this call
     // fails.
-    *display_id_out = GetID(
-        manufacturer_id, product_code_hash, output_index);
+    *display_id_out =
+        GenerateDisplayID(manufacturer_id, product_code_hash, output_index);
     // product_id is 64-bit signed so it can store -1 as kInvalidProductID and
     // not match a valid product id which will all be in the lowest 32-bits.
     if (product_id_out)
       *product_id_out = GetProductID(manufacturer_id, product_code);
     return true;
   }
   return false;
 }
 
 bool ParseOutputDeviceData(const std::vector<uint8_t>& edid,
@@ skipping 192 matching lines @@
         *flag = false;
       }
       return true;
     }
   }
 
   return false;
 }
 
 }  // namespace ui