Android O MR1 IOT Release 1.0.7 (5157592)
Merge changes If71ba334,Ia7c3ee02,I2c99fad6

* changes:
  Android Patch: ICU-20308 Define a fixed suffix without the ICU version suffix
  Cherry-pick: ICU-20309 "#if !UCONFIG_NO_CONVERSION" block should include the doxygen doc for uregex_openC
  Cherry-pick: ICU-20307 Add reldatefmt.h and compactdecimalformat.h into test/hdrtst/cxxfiles.txt