WebOTP: Launch flag

This change launches the WebOTP API to Android stable.

Bug: 670299
Change-Id: I5cd923ac9ce71ea8902a823bd7a8f8395b92f7ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2067810Reviewed-by: Victor Costan <pwnall@chromium.org>
Reviewed-by: Alex Russell <slightlyoff@chromium.org>
Commit-Queue: Victor Costan <pwnall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#755147}

third_party/blink/renderer/platform/runtime_enabled_features.json5

@@ -1626,9 +1626,7 @@
     },
     {
       name: "SmsReceiver",
-      origin_trial_feature_name: "SmsReceiver",
-      origin_trial_os: ["android"],
-      status: {"default": "experimental"},
+      status: {"default": "experimental", "Android": "stable"},
     },
     {
       name: "SquashAfterPaint",