Supports case of using style attribute for defined <clipPath>.
In SVG, <clipPath> can be used as a "clipPath" attribute or a style "clip-path".
This patch only supports "clip-path" of style is declared.
The remaining features will be added later.
[Example SVG case]
<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
viewBox="0 0 64 64" enable-background="new 0 0 64 64" xml:space="preserve">
<defs>
<clipPath id="clipPath">
<rect x="15" y="15" width="40" height="40" fill="#F00" />
<circle cx="20" cy="20" r="10" fill="#F00" />
</clipPath>
</defs>
<circle cx="25" cy="25" r="20"
style="fill: #0000ff; clip-path: url(#clipPath); " />
</svg>
we should avoid code insertion during file dependencies,
such as #include "xxx.h" which has implementations.
This could increase binary size, we can avoid it as possible.
Current patch improves binary size like this:
From: file(2059008) = text(120360) data(8096) bss(80) dec(128536)
To : file(1921832) = text(118429) data(7872) bss(56) dec(126357)
More additional patches will come in to optmize binary size.
In relation to the declaration of rx and ry attribute of rect, the following three cases occur.
rx="10" (or ry="10"
rx="10" ry = "0" (or rx="0" ry = "10")
rx="10" ry = "10"
To cover these case, we check the rx and ry declarations.
vector is designed for c++ syntaxes,
it works properly when c++ memory allocator is applied,
Here svg_loader uses c style structures which allocated using malloc()/calloc().
That brings the memory broken of stl vectors.
So, we replaced it with our customized SvgVector to easily fix it.
