We can reproduce this bug in M52/M53 across multiple devices.  Touchscreen stops working only for the page itself - other tabs or UI still work.  Switching tabs and coming back (or just waiting a little while) will make the touchscreen work on the tab again.

I was able to reproduce this on ChromeOS but not Android, so it sounds like an issue with the aura-specific touch text selection logic interacting poorly with the special nature of <select> elements.  I think that code is currently in a bit of a limbo state in terms of ownership (Chrome UI vs. input-dev).  Anyone on the CC list want to claim ownership?

I've played a bit with this yesterday. My (more reliable) repro steps (with the same html page):
1. Long-press on a text to select it and bring up selection handles;
2. Drag a selection handle and move your finger over the <select> element;
3. While still holding the selection handle, move your finger up a bit.

After this, the selection suddenly disappears which causes handles to go away. From this point on, RenderWidgetHostViewAura receives touch events but not gesture events, even after you lift your finger and start a new touch sequence.

So there are two issues here:
1. Selection is cleared when the handle is being dragged.
2. If selection is cleared while a handle is being dragged, no gesture event is received anymore. A simpler repro for this without <select> element: http://output.jsbin.com/votezuy

I will take a deeper look next week...

CL uploaded for review: https://crrev.com/2355403002.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4a024a3bfb952b02c0d0db8e52a9e7ed66df0e82

commit 4a024a3bfb952b02c0d0db8e52a9e7ed66df0e82
Author: mohsen <mohsen@chromium.org>
Date: Tue Oct 11 19:36:46 2016

Consume entire touch sequence in touch selection controller

If touch selection gets deactivated while the user is dragging a handle,
the rest of the touch sequence should be consumed by the touch selection
controller; otherwise, there would be an incomplete touch sequence which
confuses gesture recognizer. In other words, if the touch selection
controller consumes a touch press, it should consume the rest of events
in the touch sequence up until the touch release.

BUG= 642820 
TEST=See bug details

Review-Url: https://codereview.chromium.org/2355403002
Cr-Commit-Position: refs/heads/master@{#424513}

[modify] https://crrev.com/4a024a3bfb952b02c0d0db8e52a9e7ed66df0e82/ui/touch_selection/touch_selection_controller.cc
[modify] https://crrev.com/4a024a3bfb952b02c0d0db8e52a9e7ed66df0e82/ui/touch_selection/touch_selection_controller.h
[modify] https://crrev.com/4a024a3bfb952b02c0d0db8e52a9e7ed66df0e82/ui/touch_selection/touch_selection_controller_unittest.cc