VCD: Add ASH_CHROME and LACROS_CHROME

Add 2 new client types: ASH_CHROME and LACROS_CHROME and attach a
comment to keep the enum in sync with tools/metrics/histograms/enums.xml

BUG=b:176787333
TEST=Build simplechrome and deploy

Change-Id: Ib3db6feaadbc3837f46b2e9320f1fa9a61a60154
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2626852Reviewed-by: Wei Lee <wtlee@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Jasmine Chen <lnishan@google.com>
Cr-Commit-Position: refs/heads/master@{#843043}

media/capture/video/chromeos/mojom/cros_camera_service.mojom

@@ -12,6 +12,8 @@ import "media/capture/video/chromeos/mojom/camera_common.mojom";
 import "mojo/public/mojom/base/unguessable_token.mojom";
 
 // CameraClientType indicates the type of a CameraHalClient.
+// It should be kept in sync with the ChromeOSCameraClientType enum in
+// tools/metrics/histograms/enums.xml
 [Extensible]
 enum CameraClientType{
   UNKNOWN = 0,
@@ -19,6 +21,8 @@ enum CameraClientType{
   CHROME = 2,
   ANDROID = 3,
   PLUGINVM = 4,
+  ASH_CHROME = 5,
+  LACROS_CHROME = 6,
 };
 
 // CameraPrivacySwitchState indicates the state of the camera privacy switch.