The first click on the element selects it. On iOS we prevent clicks to go through on a selected element, in order to toggle the selection menu.
Created attachment 282458 [details]
Is this testable?
Attachment 282458 [details] did not pass style-queue:
ERROR: Source/WebCore/html/HTMLAttachmentElement.h:55: Place brace on its own line for function definitions. [whitespace/braces] 
Total errors found: 1 in 2 files
If any of these errors are false positives, please file a bug against check-webkit-style.
(In reply to comment #2)
> Is this testable?
Actually I think so, even without using gestures.
We already have a test that checks the selection of the attachment element. I just need to change it to reliably testing on iOS too. I'll add it to the patch before landing.
Updated test to correctly detect new behavior.
Committed revision 202835.