Minimum font size pref breaks SVG text very badly.

Minimum font size pref breaks SVG text very badly.
https://bugs.webkit.org/show_bug.cgi?id=143590.

Reviewed by Simon Fraser.

Source/WebCore:

When enabling the minimum font size perf, the computed font size is set
to the minimum font size if the computed value is smaller than the minimum.
The bug happens because the SVG text element applies its scaling on the
computed value after applying the minimum fort size rule. This means the
final computed value for the font size will be the scaling of the minimum
font size and not minimum font size itself. What we need is to postpone
applying the minimum font size rules, till the SVG scaling is applied.

Tests: svg/text/font-small-enlarged-minimum-larger.svg
       svg/text/font-small-enlarged-minimum-smaller.svg

* rendering/svg/RenderSVGInlineText.cpp:
(WebCore::RenderSVGInlineText::computeNewScaledFontForStyle): Call
computedFontSizeFromSpecifiedSizeForSVGInlineText() even if scalingFactor
is 1. We need to make sure the minimum font size rules are applied. This
function was assuming the mininum font size rule was applied when resolving
the style. This is not true anymore for the SVG text.

* style/StyleFontSizeFunctions.cpp:
(WebCore::Style::computedFontSizeFromSpecifiedSize): Do not apply the
minimum size rules for the SVG element until it applies its scaling to
the font size.

LayoutTests:

When enabling the minimum font size perf, the SVG text element should
apply the minimum font size rules on the scaled font.

* svg/text/font-small-enlarged-minimum-larger-expected.svg: Added.
* svg/text/font-small-enlarged-minimum-larger.svg: Added.
Minimum font size is larger than the scaled font size. Also the expected
file makes sure the minimum font size rules are still applied if no scaling
is applied.

* svg/text/font-small-enlarged-minimum-smaller-expected.svg: Added.
* svg/text/font-small-enlarged-minimum-smaller.svg: Added.
Minimum font size is smaller than the scaled font size. So the minimim font
size rule should not have any effect on the final computed font size.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@182876 268f45cc-cd09-0410-ab3c-d52691b4dbfc