Remove flag check for clipboard-read/write permission.query

The AsyncClipboardAPI feature flag used to control access to the entire
async clipboard API, but (since we're now shipping the text portions of
the API) its meaning has been changed to control access only to the parts
of the API that are still under development (e.g., image and delayed
generation support).

The Clipboard permission is shipping as part of the text APIs, so it
should no longer be checking this feature flag.

Bug: 677564,821947
Change-Id: Ia57b57df3eae03c2d4372cf5e7472ef1d0532f49
Reviewed-on: https://chromium-review.googlesource.com/963287Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Gary Kacmarcik <garykac@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543504}

third_party/WebKit/Source/modules/permissions/Permissions.cpp

@@ -127,11 +127,6 @@ PermissionDescriptorPtr ParsePermission(ScriptState* script_state,
     return CreatePermissionDescriptor(PermissionName::ACCESSIBILITY_EVENTS);
   }
   if (name == "clipboard-read" || name == "clipboard-write") {
-    if (!RuntimeEnabledFeatures::AsyncClipboardEnabled()) {
-      exception_state.ThrowTypeError("Async Clipboard flag is not enabled.");
-      return nullptr;
-    }
-
     PermissionName permission_name = PermissionName::CLIPBOARD_READ;
     if (name == "clipboard-write")
       permission_name = PermissionName::CLIPBOARD_WRITE;