Fix propagation of 'width' and 'height' in HTMLImageFallbackHelper

Use CSSValue::Create(const Length&, ...) to produce values in unzoomed
coordinates. This handles for instance calc(...) expressions correctly.

Bug: 860204
Change-Id: I30e639c38dc49795d44a5e28cc1bf01734543730
Reviewed-on: https://chromium-review.googlesource.com/1126307
Reviewed-by: Stephen Chenney <schenney@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#573893}
3 files changed