Generate toCSSFooValue for CSSFunctionValue and CSSSVGDocumentValue

Generate toCSSFooValue for CSSFunctionValue and CSSSVGDocumentValue

toCSSFooValue() will help to detect bad-casts as well as improve readibility.
To use DEFINE_CSS_VALUE_TYPE_CASTS, *CSS* is removed from isCSSSVGDocument()
as well as remove existing manual type cast functions.

BUG=N/A

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=158419

[gyuyoung-inactive, 2013-09-27 04:04:14]

new patch to remove static_cast<CSS*Value>

[tkent, 2013-09-27 04:12:48]

lgtm

[commit-bot: I haz the power, 2013-09-27 04:13:00]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/gyuyoung.kim@samsung.com/24954002/1

[commit-bot: I haz the power, 2013-09-27 06:03:25]

Commit queue rejected this change because the description was changed
between the time the change entered the commit queue and the time it
was ready to commit. You can safely check the commit box again.

[commit-bot: I haz the power, 2013-09-27 06:04:44]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/gyuyoung.kim@samsung.com/24954002/1

[commit-bot: I haz the power, 2013-09-27 06:05:01]

Change committed as 158419