Bug 1153193 - Add EXTRA_DEVICES_ONLY flag to share intents. r=rnewman

Before we only added this flag to the share intent used by the browser toolbar
menu.

Practically, this has the effect of having "Add to <current channel>" opening
the share overlay with *only* the device list wherever getShareIntent() is
used. Ideally, this method is used anywhere we use ACTION_SEND.

I've noticed this change makes both sharing from the long-press context menu
and about:reader to display *only* the device list.

--HG--
extra : rebase_source : 63fd4c7ebfa43ed3f2f7fc3d0ef9809a5458aa9f

mobile/android/base/GeckoAppShell.java

@@ -43,6 +43,7 @@ import org.mozilla.gecko.mozglue.JNITarget;
 import org.mozilla.gecko.mozglue.RobocopTarget;
 import org.mozilla.gecko.mozglue.generatorannotations.OptionalGeneratedParameter;
 import org.mozilla.gecko.mozglue.generatorannotations.WrapElementForJNI;
+import org.mozilla.gecko.overlays.ui.ShareDialog;
 import org.mozilla.gecko.prompts.PromptService;
 import org.mozilla.gecko.util.EventCallback;
 import org.mozilla.gecko.util.GeckoRequest;
@@ -1162,6 +1163,7 @@ public class GeckoAppShell
         Intent shareIntent = getIntentForActionString(Intent.ACTION_SEND);
         shareIntent.putExtra(Intent.EXTRA_TEXT, targetURI);
         shareIntent.putExtra(Intent.EXTRA_SUBJECT, title);
+        shareIntent.putExtra(ShareDialog.INTENT_EXTRA_DEVICES_ONLY, true);
 
         // Note that EXTRA_TITLE is intended to be used for share dialog
         // titles. Common usage (e.g., Pocket) suggests that it's sometimes