ICU: Drop test/ version of DecimalFormat_ICU58 and friends.

The three ICU classes lived in the test source tree but
in the same package as code under test (android.icu.text,
after transformation, which is in libcore). This is not
supported in the new OpenJDK 9 based build toolchain.
This CL drops the three offending classes.

CL http://r.android.com/527815
(commit ea5ab8c8d4e81cd27d0c3d2970f082da66170ea2)
introduced copies, DecimalFormat_ICU58_Android and
DigitList_Android and moved libcore to them. Since
then, the original classes are not used by libcore.

This CL migrates remaining uses (in ICU tests) of
DecimalFormat_ICU58 to use DecimalFormat_ICU58_Android
instead. The migration is done via a ReplaceTypeName
processor; since the AST callbacks observe both
unqualified and qualified references to the type
name, both need to be replaced; the class name is
unique within ICU, so this simple approach works.
Alternatively, a local patch to NumberFormat*Test.java
would also have worked, but this was not done.

Test: tools/srcgen/generate_android_icu4j.sh
Test: Treehugger
Test: CtsIcuTestCases
Bug: 68696705
Change-Id: I5ba0b3497ba896b83ee1616a78cb6dab758dfa6d
8 files changed