Adds woff header checks
Adds woff header checks

Add some woff header checks to pass W3C WOFF User Agent test suite.
http://w3c-test.org/framework/suite/woff-ua/

The following testcases should pass by adding this checks.
- blocks-extraneous-data-00[1-7]
- blocks-overlap-00[1-3]
- directory-extraneous-data-001
- directory-overlaps-00[34]
- header-totalSfntSize-00[13]

The CL will make OTS pass all testcases execpt for directory-4-byte-002.
OTS intentionally doesn't pass directory-4-byte-002 to workaround a font
generator bug. See http://crbug.com/47960 for details.

BUG=chromium:109813
TEST=Checked 291 testcases at http://w3c-test.org/framework/suite/woff-ua/ manually.

Review URL: http://codereview.chromium.org/9193002/


jgedler/ots,jgedler/ots,a19810227/ots,a19810227/ots,a19810227/ots,jgedler/ots