Renamed some duplicate symbols in Blink paint timing code

image_paint_timing_detector.cc and text_paint_timing_detector.cc
are similar and had identically named helper functions. This
broke some jumbo builds. This patch renames the helper functions
to have unique names.

Bug: 869924
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I0a42ef4f647ea0b5bfb80bf9dc363a0650424efd
Reviewed-on: https://chromium-review.googlesource.com/c/1268135
Reviewed-by: Fredrik Söderquist <fs@opera.com>
Commit-Queue: Daniel Bratell <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#597517}
2 files changed