This is due to how the hud layer is setup. In spv1 mode we build property trees from the layers. In spv2 mode, the hud layer is created without properties, and then we skip property tree generation.

One way to fix this is to manually assign property trees for the hud layer in cc. This could be brittle, but is straightforward.

@Ali, do you have opinions about how to best solve this?

I'd lean towards assigning property tree ids manually, assuming it's straightforward (e.g. if these ids can be defined as constants somewhere) and that the hud layer itself doesn't lead to the creation of property tree nodes.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/cccbe41d5ebad5b6e7789c9a18cbdb1bf3b06794

commit cccbe41d5ebad5b6e7789c9a18cbdb1bf3b06794
Author: pdr <pdr@chromium.org>
Date: Thu Mar 23 23:58:26 2017

Build property trees for the HUD layer when using layer lists

When using layer lists in the compositor (aka, SPV2 mode), the hud
layer created in the layer tree host will not have property tree
nodes set. This patch ensures these nodes are set by the layer tree
host.

With this patch, running with the following flags does not crash:
--enable-slimming-paint-v2 --show-paint-rects

BUG= 698066 
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2776473002
Cr-Commit-Position: refs/heads/master@{#459287}

[modify] https://crrev.com/cccbe41d5ebad5b6e7789c9a18cbdb1bf3b06794/cc/trees/layer_tree_host.cc
[modify] https://crrev.com/cccbe41d5ebad5b6e7789c9a18cbdb1bf3b06794/cc/trees/layer_tree_host_unittest.cc

We no longer crash in devtools.

Followup raster invalidation rect work is being tracked in  https://crbug.com/704598