[Bluetooth] Do not reverse BT address from HID ID

The ID from /sys/class/power_supply/hid-{btaddr}-battery is already in
the correct order so there is no need to reverse it. Tested with Apple
Magic Mouse.

Bug: b:161733238
Change-Id: Iad98f1ba016fee70f4fa9b2280f975dacf24bea4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2308855Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Sonny Sasaka <sonnysasaka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792335}

ash/power/hid_battery_listener_unittest.cc

@@ -19,7 +19,7 @@ namespace ash {
 namespace {
 
 const char kPath[] = "/sys/class/power_supply/hid-AA:BB:CC:DD:EE:FF-battery";
-const char kAddress[] = "ff:ee:dd:cc:bb:aa";
+const char kAddress[] = "aa:bb:cc:dd:ee:ff";
 const char kDeviceName[] = "test device";
 
 }  // namespace

ash/power/hid_battery_util.cc

@@ -53,11 +53,7 @@ std::string ExtractBluetoothAddressFromHIDBatteryPath(const std::string& path) {
   if (!RE2::FullMatch(identifier, kBluetoothAddressRegex))
     return std::string();
 
-  std::string reverse_address = base::ToLowerASCII(identifier);
-  std::vector<base::StringPiece> result = base::SplitStringPiece(
-      reverse_address, ":", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
-  std::reverse(result.begin(), result.end());
-  return base::JoinString(result, ":");
+  return base::ToLowerASCII(identifier);
 }
 
 }  // namespace ash

ash/power/hid_battery_util_unittest.cc

@@ -45,7 +45,7 @@ TEST_F(HidBatteryUtilTest, ExtractBluetoothAddressFromHIDBatteryPath) {
             ExtractBluetoothAddressFromHIDBatteryPath(
                 "/sys/class/power_supply/hid-A00:b1:C2:d3:E4:f5-battery"));
 
-  EXPECT_EQ("f5:e4:d3:c2:b1:a0",
+  EXPECT_EQ("a0:b1:c2:d3:e4:f5",
             ExtractBluetoothAddressFromHIDBatteryPath(
                 "/sys/class/power_supply/hid-A0:b1:C2:d3:E4:f5-battery"));
 }

ash/system/power/peripheral_battery_notifier_unittest.cc

@@ -30,10 +30,10 @@ namespace {
 // HID device.
 const char kTestBatteryPath[] =
     "/sys/class/power_supply/hid-AA:BB:CC:DD:EE:FF-battery";
-const char kTestBatteryAddress[] = "ff:ee:dd:cc:bb:aa";
+const char kTestBatteryAddress[] = "aa:bb:cc:dd:ee:ff";
 const char kTestDeviceName[] = "test device";
 const char kTestBatteryId[] =
-    "battery_notification_bluetooth-ff:ee:dd:cc:bb:aa";
+    "battery_notification_bluetooth-aa:bb:cc:dd:ee:ff";
 
 // Bluetooth devices.
 const char kBluetoothDeviceAddress1[] = "aa:bb:cc:dd:ee:ff";
@@ -218,9 +218,9 @@ TEST_F(PeripheralBatteryNotifierTest, InvalidBatteryInfo) {
 TEST_F(PeripheralBatteryNotifierTest, ExtractBluetoothAddress) {
   const std::string bluetooth_path =
       "/sys/class/power_supply/hid-A0:b1:C2:d3:E4:f5-battery";
-  const std::string expected_bluetooth_address = "f5:e4:d3:c2:b1:a0";
+  const std::string expected_bluetooth_address = "a0:b1:c2:d3:e4:f5";
   const std::string expected_bluetooth_id =
-      "battery_notification_bluetooth-f5:e4:d3:c2:b1:a0";
+      "battery_notification_bluetooth-a0:b1:c2:d3:e4:f5";
   const std::string non_bluetooth_path =
       "/sys/class/power_supply/hid-notbluetooth-battery";