Add all g1 files that compiles with `$(CFLAGS_CONVERSION_WARNINGS)`. Remove the
old example
`g1Numa.cpp`, because I misspelled `g1NUMA.cpp` (that does not compile with the
warnings)
Eventually, after cleanups, there will only be a single expression left
```$(call ExtendFlags, $(TOPDIR)/src/hotspot/share/gc/g1, \
%.cpp, _CXXFLAGS, $(CFLAGS_CONVERSION_WARNINGS)), ```
---------
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Interim AI Policy](https://openjdk.org/legal/ai).
-------------
Commit messages:
- remove trash file
- G1: Enable stricter warning flags for g1 files
Changes: https://git.openjdk.org/jdk/pull/30924/files
Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=30924&range=00
Issue: https://bugs.openjdk.org/browse/JDK-8382506
Stats: 116 lines in 2 files changed: 114 ins; 0 del; 2 mod
Patch: https://git.openjdk.org/jdk/pull/30924.diff
Fetch: git fetch https://git.openjdk.org/jdk.git pull/30924/head:pull/30924
PR: https://git.openjdk.org/jdk/pull/30924
