Remove special case for transparent SVG root layers

This patch fixes a bug where opacity would be applied twice on root
SVG elements that had a layer. The special-case for SVG in
RenderLayer::isTransparent() has been removed and the implementation
has been moved to the header. prepareToRenderSVGContent has been
updated to not create a transparency layer for the root SVG element,
as it will be handled by RenderLayer.

BUG=373808

Review URL: https://codereview.chromium.org/288253002

git-svn-id: svn://svn.chromium.org/blink/trunk@174102 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Change the way ImageDecodingStore is allocated and destroyed

ImageDecodingStore is now initialized atomically. It is leaked when
the process exits. This allows safe use from multiple threads.

BUG=369808

Review URL: https://codereview.chromium.org/284993002

git-svn-id: svn://svn.chromium.org/blink/trunk@174103 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: For non-lossless console.table() also print the data object.

This is to access printed objects inside console.table().
Also print the data object when console.table() would print nothing.

BUG=306120
R=pfeldman

Review URL: https://codereview.chromium.org/290473003

git-svn-id: svn://svn.chromium.org/blink/trunk@174104 bbb929c8-8fbe-4397-9dbb-9b2b20218538