Do not include DroidSansFallback on EXTENDED_FONT_FOOTPRINT builds.

The build file is modified to hang non-module fonts on DroidSansMono
instead, now that a device may not have DroidSansFallback.  Also, some
cleanup is done to make the rules clearer and keep usages near definitions.

The support for following character will disappear from the extended
profiles because of this change:
U+202A          LEFT-TO-RIGHT EMBEDDING
U+202B          RIGHT-TO-LEFT EMBEDDING
U+202C          POP DIRECTIONAL FORMATTING
U+202D          LEFT-TO-RIGHT OVERRIDE
U+F95A  讀      CJK COMPATIBILITY IDEOGRAPH-F95A
U+F9F3  麟      CJK COMPATIBILITY IDEOGRAPH-F9F3
U+10400 𐐀       DESERET CAPITAL LETTER LONG I
U+10428 𐐨       DESERET SMALL LETTER LONG I
U+1044D 𐑍       DESERET SMALL LETTER ENG
U+1044E 𐑎       DESERET SMALL LETTER OI
U+1044F 𐑏       DESERET SMALL LETTER EW

The first four are not needed, as HarfBuzz makes sure they are rendered as
invisible, the two CJK compatibility characters have canonnical
decompositions to unified ideographs already supported in included Noto Sans
CJK fonts, and the Deseret letters were only in DroidSansFallback for
testing purposes.

Change-Id: Ibb7fa61dc851710ba14c3944281e228bd2e4f5b2
1 file changed