Allow origin trials to be enabled by script

third_party/WebKit/LayoutTests/VirtualTestSuites

 [
   {
     "prefix": "color_space",
     "base": "fast/canvas/color-space",
     "args": ["--enable-color-correct-rendering",
              "--enable-true-color-rendering"]
   },
   {
     "prefix": "gpu",
     "base": "fast/canvas",
@@ skipping 86 matching lines @@
     "prefix": "stable",
     "base": "media/stable",
     "args": ["--stable-release-mode"]
   },
   {
     "prefix": "stable",
     "base": "paint/invalidation",
     "args": ["--stable-release-mode"]
   },
   {
+    "prefix": "stable",
+    "base": "http/tests/origin_trials/webexposed",
+    "args": ["--stable-release-mode"]
+  },
+  {
+    "prefix": "origin-trials-features-disabled",
+    "base": "http/tests/origin_trials/webexposed",
+    "args": ["--disable-blink-features=ForeignFetch,ImageCapture,LinkServiceWorker,LongTaskObserver,ServiceWorkerNavigationPreload,SetRootScroller,WebUSB,WebVR,WebShare",
+             "--disable-features=ForeignFetch,ImageCapture,LinkServiceWorker,LongTaskObserver,ServiceWorkerNavigationPreload,SetRootScroller,WebUSB,WebVR,WebShare"]
+  },
+  {
     "prefix": "android",
     "base": "fullscreen",
     "args": ["--enable-threaded-compositing",
              "--enable-fixed-position-compositing", "--enable-prefer-compositing-to-lcd-text",
              "--enable-composited-scrolling-for-frames", "--enable-gesture-tap-highlight", "--enable-pinch",
              "--force-overlay-fullscreen-video", "--enable-overlay-scrollbars", "--enable-overscroll-notifications",
              "--enable-fixed-layout", "--enable-viewport", "--disable-canvas-aa",
              "--disable-composited-antialiasing"]
   },
   {
@@ skipping 237 matching lines @@
     "prefix": "mojo-localstorage",
     "base": "external/wpt/webstorage",
     "args": ["--mojo-local-storage"]
   },
   {
     "prefix": "mojo-localstorage",
     "base": "storage/domstorage/localstorage",
     "args": ["--mojo-local-storage"]
   }
 ]