Revert of Add the GeometricPrecisionDisablesTypesettingFeatures flag (https://codereview.chromium.org/141433027/)

Reason for revert:
Reverting because typesetting features are actually important for readable text. We will need to tackle the performance issue in a different way.

Original issue's description:
> Add the GeometricPrecisionDisablesTypesettingFeatures flag
> 
> This patch adds the runtime enabled feature "GeometricPrecisionDisablesTypesettingFeatures"
> which disables kerning and ligatures for text with text-rendering=
> geometricPrecision. This matches the spec [1]. If there are no major
> regressions we will remove this flag in roughly 6 weeks (~1 release).
> 
> [1] https://svgwg.org/svg2-draft/single-page.html#painting-TextRenderingProperty
> 
> BUG=338870
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=166037

TBR=eae@chromium.org,eae@google.com,leviw@google.com
NOTREECHECKS=true
NOTRY=true
BUG=338870

Review URL: https://codereview.chromium.org/142413011

git-svn-id: svn://svn.chromium.org/blink/trunk@166047 bbb929c8-8fbe-4397-9dbb-9b2b20218538