move SK_MMAP_SUPPORT into SkPreConfig, so we can know about its availability
throughout the code.

Add SkData::NewFromMMap() help factory.

Refactor (now gone) SkMMapStream into SkStream::NewFromFile() factory
Review URL: https://codereview.chromium.org/12919013

git-svn-id: http://skia.googlecode.com/svn/trunk/include@8200 2bbb7eff-a529-9590-31e7-b0007b416f81
4 files changed