Inline static Create() in classes from renderer/core/css/cssom

Removes trivial Create() methods from classes defined in
renderer/core/css/cssom, and leaves non-trivial cases unchanged.

Affected classes: ComputedStylePropertyMap, CSSNumericArray,
CSSUnsupportedColorValue and CSSUnsupportedStyleValue.

Some highlights:

* Create() methods for ComputedStylePropertyMap and CSSNumericArray
  were apparently unused.

* In CSSUnsupportedStyleValue, an extra constructor is added to
  keep clients' legibility.

* CSSUnsupportedColorValue::FromCSSValue was being used as a static
  Create method of sorts so it is also being inlined. An extra
  constructor is added to preserve the semantics of FromCSSValue().

Bug: 939691
Change-Id: I0b2212b71053a0c15fd70ae266abeb83f54e0a00
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1962861
Reviewed-by: Anders Hartvoll Ruud <andruud@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Jacobo Aragunde Pérez <jaragunde@igalia.com>
Cr-Commit-Position: refs/heads/master@{#724171}
10 files changed