Image Capture: clarify idl flags

third_party/WebKit/Source/platform/RuntimeEnabledFeatures.json5

 {
   // http://dev.chromium.org/blink/runtime-enabled-features
   //
   // This list is used to generate RuntimeEnabledFeatures.h/cpp which contains
   // a class that stores static enablers for all experimental features.
 
   parameters: {
     // Each feature can be assigned a "status":
     // status=stable -> Enable this in all Blink configurations.  We are committed to these APIs indefinitely.
     // status=experimental -> In-progress features, Web Developers might play with, but are not on by default in stable.
@@ skipping 523 matching lines @@
       name: "MediaConstraints",
       status: "stable",
     },
     {
       name: "MediaDocumentDownloadButton",
     },
     {
       name: "MediaGetSettings",
       status: "stable",
     },
+    {
+      name: "MediaQueryShape",
+      status: "experimental",
+    },
     // MediaSession is enabled by default on Android only.
     // TODO(rbyers): Add parameter to specify platform.
     {
       name: "MediaSession",
       status: "test",
     },
     {
       name: "MediaSourceExperimental",
       status: "experimental",
     },
     {
       name: "MediaSourceNewAbortAndDuration",
       status: "experimental",
     },
     {
       name: "MediaStreamSpeech",
       status: "experimental",
     },
     {
-      name: "MediaQueryShape",
-      status: "experimental",
-    },
-    {
       name: "MediaStreamTrackContentHint",
       status: "experimental",
     },
     {
+      name: "MediaTrackCapabilities",
+      implied_by: ["ImageCapture"],
+      status: "experimental",
+    },
+    {
       name: "MemoryInfoInWorkers",
       status: "experimental",
     },
     // This is enabled by default on Windows only. The only part that's
     // "experimental" is the support on other platforms.
     {
       name: "MiddleClickAutoscroll",
       status: "test",
     },
     {
@@ skipping 441 matching lines @@
     {
       name: "BlockLegacySubresources",
       status: "experimental",
     },
     {
       name: "MediaControlsOverlayPlayButton",
       settable_from_internals: true,
     }
   ],
 }