Add back mistakenly removed content scene to intent filter

In https://chromium-review.googlesource.com/c/chromium/src/+/974445 I
failed to notice that the content scheme was only on the intent filter
with mime types. Assuming this was intentionally only on the filter
with mime types, I've added it back to that filter.

Bug: 827796
Change-Id: I6b1f9dc1b01e6b87838215698290d7ac8d894022
Reviewed-on: https://chromium-review.googlesource.com/995957Reviewed-by: Ted Choc <tedchoc@chromium.org>
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548088}

chrome/android/java/AndroidManifest.xml

@@ -198,6 +198,7 @@ by a child template that "extends" this file.
             <intent-filter>
                 {% block common_view_intent_shared_filter_with_mime_body %}
                 {{ self.common_view_intent_shared_filter_body() }}
+                <data android:scheme="content" />
                 <data android:mimeType="text/html"/>
                 <data android:mimeType="text/plain"/>
                 <data android:mimeType="application/xhtml+xml"/>