Convert SpdyControlType to SpdyFrameType

Remove NUM_CONTROL_FRAME_TYPES (used to indicate a data frame) and
replace it with a DATA enum value.

Also add {FIRST,LAST}_CONTROL_TYPE enum values and use them in checks.

Strengthen error checking in spdy_framer.cc -- previously, converting
to an enum type may inadvertently convert an invalid value to a
valid one.

This lands server change 45004245.

Also take advantage of new enum values in some test functions.

Review URL: https://codereview.chromium.org/13849003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193145 0039d316-1c4b-4281-b951-d872f2087c98
11 files changed