Swap the chess king and queen glyphs in Droid Sans Fallback.

Also remove the unused DroidSansFallbackLegacy.ttf.

Based on public bug report
https://code.google.com/p/android/issues/detail?id=71389.
The original glyphs were mistakenly swapped.

Following is the code that was run on the font:

import sys
from fontTools import ttLib
WHITE_KING = 0x2654
WHITE_QUEEN = 0x2655
BLACK_KING = 0x265A
BLACK_QUEEN = 0x265B
font_name = sys.argv[1]
font = ttLib.TTFont(font_name)
for table in font['cmap'].tables:
  cmap = table.cmap
  cmap[WHITE_KING], cmap[WHITE_QUEEN] = cmap[WHITE_QUEEN], cmap[WHITE_KING]
  cmap[BLACK_KING], cmap[BLACK_QUEEN] = cmap[BLACK_QUEEN], cmap[BLACK_KING]
font.save(font_name+'-fixed')

Bug: 15643969
Change-Id: Iacee3d72ef8146016e15828f051822460ae2ff4e