Subset Droid Sans Fallback to remove duplicate coverage.

Removes all characters that are already supported by either Roboto or the
expanded Noto Sans Symbols font.  The Droid Sans Fallback fonts are also
passed through the fonttools subsetter to recompress the tables and convert
the post table to version 3.0.  This change reduces the size of the files by
about 270KB each.

The following characters are removed:
0021..007E, 00A0..00A1, 00A4, 00A7..00A8, 00AA..00AB, 00AD..00B4,
00B6..00BF, 00C6, 00D0, 00D7..00D8, 00DE..00E1, 00E6, 00E8..00EA,
00EC..00ED, 00F0, 00F2..00F3, 00F7..00FA, 00FC, 00FE, 0101, 0111, 0113,
011B, 0126..0127, 012B, 0131..0133, 0138, 013F..0142, 0149..014B, 014D,
0152..0153, 0166..0167, 016B, 01C0..01C3, 01CE, 01D0, 01D2, 01D4, 01D6,
01D8, 01DA, 01DC, 021A..021B, 0250..02B2, 02B4, 02B7, 02BB..02BC,
02C7..02CD, 02D0..02D1, 02D8..02DB, 02DD..02DE, 02E0, 02E4, 0300..0301,
0303..0304, 0306, 0308, 030A..030B, 030F..0334, 0339..033D, 035C, 0361,
0391..03A1, 03A3..03A9, 03B1..03C1, 03C3..03C9, 0401, 0410..044F, 0451,
200C..2011, 2013..2016, 2018..2019, 201C..201D, 2020..2022, 2025..2027,
2030, 2032..2033, 2035, 203B..203C, 203E, 2047..2049, 2074, 207F,
2081..2084, 20A0..20B9, 2103, 2105, 2109, 2111, 2113, 2116, 2118, 211C,
2121..2122, 2126, 212B, 2133, 2135, 2153..2154, 215B..215E, 2160..216B,
2170..2179, 2190..2200, 2202..2203, 2205, 2207..2209, 220B..220C, 220F,
2211, 2215, 2217, 221A, 221D..2220, 2223, 2225, 2227..222C, 222E,
2234..2237, 223C..223D, 2245, 2248, 224C, 2252, 2260..2261, 2264..2267,
226A..226B, 226E..226F, 2282..2287, 2295, 2297, 2299, 22A5, 22BF, 22C5,
2308..230B, 2312, 23AF, 2460..24B5, 24D0..24E9, 2500..254B, 2550..2574,
2581..258F, 2592..2595, 25A0..25A1, 25A3..25AA, 25B2..25B3, 25B6..25B7,
25BA, 25BC..25BD, 25C0..25C1, 25C6..25C9, 25CB, 25CE..25D1, 25E2..25E6,
25EF, 2605..2606, 260E..260F, 261C, 261E, 2640, 2642, 2654..266A,
266C..266D, 266F, 2680..2685, 2701..2704, 2706..2709, 270C..2727,
2729..274B, 274D, 274F..2752, 2756, 2758..275E, 2761..2794, 2798..27AF,
27B1..27BE, 2985..2986, 3008..3009, FFFD

Bug: 15348046
Change-Id: I1d4751b6f79a4c6de23910c983f2f09c9460b160