* Update the pre-built ICU data files for all platforms

  source/data/in/icudtl.dat for non-Android platforms
  {linux,mac}/icudt*.S for linux/mac
  android/icudtl.dat and android/icudt*.S for Android
  windows/icudt.dll for Windows

* Update Android data trimming script

  1. Make sure that 'default' calendar is kept in locales where it's relevant
    : root, th, fa, ar_SA, etc.
  2. Add a minimal region data to work around a bug in ICU with pool.res
     handling

* Update gn and gyp files
* And add a TODO comment to update.sh to automate the build file update.
* Add it_CH to the locale list.
* Add sr_Latn to unit/reslocal.mk (required by sh) and
  line_normal_fi to brkitr/brklocal.mk (referred to in brkitr/fi.txt) in
  place of line_fi.

* Update and add scripts for data building
* Completely rewrite README.chromium
* Check-in the prebuilt ICU data files/assembly sources for
  Linux,Mac,Windows,Chrome OS and Android.

BUG=575007
TEST=Blink layout tests, webkit unittests
TEST=All bots can build successfully
TEST=net_unittests --gtest_filter="*ilenameUtil*"
TEST=net_unittests --gtest_filter="*IDN*" (pending bug 336973)
TEST=base_unittests --gtest_filter="*Conv*"
TEST=browser_tests --gtest_filter="*ncoding*"
TEST=base_unittests --gtest_filter="*essage*"
TEST=ui_base_unittests --gtest_filter="*ormat*"
TEST=ui_base_unittests --gtest_filter="L10n*"
R=mark@chromium.org

Review URL: https://codereview.chromium.org/1639543006 .

A. Converter update per HTML encoding spec along with changes in
  the encoding name alias table.
B. Remove all the codes for converters Blink and Chromium do not need
(SCSU, Lotus, ISO-2022-xx other than JP, BOCU, UTF-7, etc).

This is reapplying the following CLs (that we used for ICU 52.1) to ICU 54.1 :

https://codereview.chromium.org/598383002
https://codereview.chromium.org/654153002

We have two upstream bugs filed for A and B above:
  http://www.icu-project.org/trac/ticket/11296
  http://www.icu-project.org/trac/ticket/10303

In addiition to A and B, we unified Big5 and Big5-HKSCS per
the encoding spec (bug 277868). That also includes properly supporting
the four 2-character sequences ( see http://crbug.com/277868#c3 ).
big5_gen.sh deviates from the current spec to work around a bug
in the spec. (see https://www.w3.org/Bugs/Public/show_bug.cgi?id=27878)

Moreover, ucmlocal.mk is added to list only encodings we want to support.

Also, tighten the state table for windows-946-2000.ucm that we use
for EUC-KR for now. And, drop 'base' map for windows-{936,949}-2000.ucm.

Finally, add euc-kr-html.ucm along with scripts/euckr_gen.sh, but
it is not yet used pending the resolution of bug 450312.

Data size checkpoint: 20,566,864 bytes (the original ICU 54=25,343,024)

BUG=277868, 428145, 450312
TEST=net_unittests --gtest_filter="*ilenameUtil*"
TEST=base_unittests --gtest_filter="*Conv*"
TEST=browser_tests --gtest_filter="*ncoding*"
TEST=Blink: fast/encoding/*
R=jsbell@chromium.org, mark@chromium.org

Review URL: https://codereview.chromium.org/839713003

1. Replace the current encoding alias list (heavily patched) with our own
HTML5-specific alias list. It's mostly generated from encoding.json, which
is in turn derived from the WHATWG Encoding living standard. The most notable
difference is that UTF-32 entries are kept until bug 417850 is resolved.
Two other differences are:

 a. Two aliases for iso-8859-8-i (logical and csiso88598i) are not listed.
 They're dealt with in Blink.

 b. Chinese (gb*, big5*) aliases are not yet aligned to the encoding
spec pending our decision on the unification of Big5 / Big5-HKSCS and
GBK / GB18030.

2. Replace all the single-byte mapping tables with what's automatically
generated with scripts/single-byte-gen.sh that uses index-* files downloaded
from the WHATWG spec site. This will fix the decoding (ToUnicode) of
windows-874 and windows-1253 while removing a lot of fallback/spurrious
mapping entries in encoding direction ('FromUnicode') in a number of encodings.

3. Regenerate the ICU binary data files for Linux/Mac/Android/Windows/CrOS.

4. Remove now obsolete noop-*ucm files used to make ISO-2022-CN* decoder
to turn an empty string. They're not necessary any more because ISO-2022-CN*
were made 'replacement' encodings in Blink and our version of ICU does not
have any code for ISO-2022-CN* any more.

This cuts down the data size by 15kB. On Android, there's virtually
no change in the data size because the previous data file on Android
accidentally had smaller locale data for nb and ms.

BUG=412053
TEST=browser_tests --gtest_filter="*ncoding*"
TEST=net_unittest --gtest_filter="*ilenameUtil*"
TEST=base_unittests --gtest_filter="*Conv*"
TEST=Blink: fast/encoding/*
TEST=http://www.w3.org/International/tests/repository/encoding/indexes/results-indexes
TEST=http://www.w3.org/International/tests/repository/encoding/indexes/results-aliases
TEST=http://www.w3.org/International/tests/repository/run?manifest=encoding/indexes&test=windows-1253_test
TEST=http://www.w3.org/International/tests/repository/run?manifest=encoding/indexes&test=windows-874_test
R=jsbell@chromium.org

Review URL: https://codereview.chromium.org/598383002

git-svn-id: http://src.chromium.org/svn/trunk/deps/third_party/icu52@292447 4ff67af0-8c30-449e-8e8b-ad334ec8d88c