[Android WebAPK] Ignore com.android.browser.headers intent extra for Webapps and WebAPKs

This CL removes the handling of the com.android.browser.headers intent extra in
WebappActivity. The handling was added in
https://chromium-review.googlesource.com/c/chromium/src/+/1116219
at the time that TWAs used WebappActivity. They no longer do so.

BUG=871266, 801487

Cq-Include-Trybots: luci.chromium.try:ios-simulator-cronet;luci.chromium.try:ios-simulator-full-configs
Change-Id: Ife40f882f45900f33ff356c435ee1a9283a4419e
Reviewed-on: https://chromium-review.googlesource.com/c/1288012
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Peter Conn <peconn@chromium.org>
Commit-Queue: Peter Kotwicz <pkotwicz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601176}
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
index 85dca7b..24389eb 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/webapps/WebappActivity.java
@@ -134,9 +134,6 @@
     private static LoadUrlParams createLoadUrlParams(WebappInfo info, Intent intent) {
         LoadUrlParams params =
                 new LoadUrlParams(info.uri().toString(), PageTransition.AUTO_TOPLEVEL);
-        String headers = IntentHandler.getExtraHeadersFromIntent(intent, true);
-        if (headers != null) params.setVerbatimHeaders(headers);
-
         return params;
     }