Chrome OS: Add key code for privacy screen toggle

Some upcoming Chromebooks will have an electronic privacy screen which
can be toggled on or off via a hotkey. When this key is pressed linux
will emit a KEY_PRIVACY_SCREEN_TOGGLE keycode 0x279. There is not
currently a USB HID usage for privacy screen control but there is a
request in progress and is expected to be in the 0x300 range of the
consumer page. We use the next available device DomKey 0x60C and the
next unused VKEY 0x9B.

BUG=b:146006851, b:138397511, 952051

Change-Id: Ia519c6227ca1acf3f352ef1d757b0ef3925dca05
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1979232
Commit-Queue: Mathew King <mathewk@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: Gil Dekel <gildekel@chromium.org>
Reviewed-by: Kevin Schoedel <kpschoedel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#733021}

ui/events/keycodes/dom/dom_code_data.inc

@@ -103,6 +103,12 @@ DOM_CODE_DECLARATION {
   DOM_CODE(0x000014, 0x0000, 0x0000, 0x0000, 0xffff, "Suspend", SUSPEND),
   DOM_CODE(0x000015, 0x0000, 0x0000, 0x0000, 0xffff, "Resume", RESUME),
   DOM_CODE(0x000016, 0x0000, 0x0000, 0x0000, 0xffff, "Turbo", TURBO),
+  // TODO(b/146683484): HID usage for privacy screen control is not yet
+  // approved. Once it is update the code here.
+  // TODO(https://crbug.com/952051): Privacy screen will not have a DOM |code|
+  // name defined as it is not exposed to web content.
+  DOM_CODE(0x000017, 0x0279, 0x0281, 0x0000, 0xffff, "PrivacyScreenToggle",
+             PRIVACY_SCREEN_TOGGLE),  // Privacy Screen Toggle
 
   // =========================================
   // USB Usage Page 0x01: Generic Desktop Page

ui/events/keycodes/dom/keycode_converter_unittest.cc

@@ -24,8 +24,8 @@ namespace {
 // These are in the same order as the columns in dom_code_data.inc
 // as reflected in the DOM_CODE() macro below.
 const size_t expected_mapped_key_count[] = {
-  212,  // evdev
-  212,  // xkb
+  213,  // evdev
+  213,  // xkb
   157,  // windows
   118,  // mac
 };

ui/events/keycodes/dom_us_layout_data.h

@@ -417,6 +417,10 @@ const struct DomCodeToKeyboardCodeEntry {
     // DomCode::SUSPEND                            0x000014 Suspend
     // DomCode::RESUME                             0x000015 Resume
     // DomCode::TURBO                              0x000016 Turbo
+#if defined(OS_POSIX)
+    {DomCode::PRIVACY_SCREEN_TOGGLE,
+     VKEY_PRIVACY_SCREEN_TOGGLE},               // 0x000017 PrivacyScreenToggle
+#endif
     {DomCode::SLEEP, VKEY_SLEEP},               // 0x010082 Sleep
     // DomCode::WAKE_UP                            0x010083 WakeUp
     {DomCode::US_A, VKEY_A},                   // 0x070004 KeyA

ui/events/keycodes/keyboard_codes_posix.h

@@ -220,6 +220,7 @@ enum KeyboardCode {
   VKEY_POWER = 0x98,
   VKEY_ASSISTANT = 0x99,
   VKEY_SETTINGS = 0x9A,
+  VKEY_PRIVACY_SCREEN_TOGGLE = 0x9B,
   VKEY_BRIGHTNESS_DOWN = 0xD8,
   VKEY_BRIGHTNESS_UP = 0xD9,
   VKEY_KBD_BRIGHTNESS_DOWN = 0xDA,

ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine_unittest.cc

@@ -819,6 +819,7 @@ TEST_F(XkbLayoutEngineVkTest, KeyboardCodeForNonPrintable) {
     // known to XKB.
     {{DomCode::LAUNCH_ASSISTANT, EF_NONE}, VKEY_ASSISTANT},
     {{DomCode::LAUNCH_CONTROL_PANEL, EF_NONE}, VKEY_SETTINGS},
+    {{DomCode::PRIVACY_SCREEN_TOGGLE, EF_NONE}, VKEY_PRIVACY_SCREEN_TOGGLE},
     // Verify that number pad digits produce located VKEY codes.
     {{DomCode::NUMPAD0, EF_NONE, XKB_KEY_KP_0, '0'}, VKEY_NUMPAD0},
     {{DomCode::NUMPAD9, EF_NONE, XKB_KEY_KP_9, '9'}, VKEY_NUMPAD9},