Build the entry_points_json_files in debug mode as well

[mkustermann]

The "flutter build apk/aot" command accepts all three modes (--debug,
--profile, --release). This implies we need the entry_points_json_files
target also in "debug" mode (currently the build fails with an exception).

[mkustermann]

/cc @mraleph

[alexmarkov]

@mkustermann, I tried this when enabling TFA in Flutter (#4725).
Apparently it didn't work on ios/debug, where simdbc target is used, which doesn't support precompilation (at least it didn't support at that time). Consider building the engine on Mac in debug mode to test if it works now.

Also, you might need to modify infra script (in chrome infra repo) which packages built artifacts in order to make entry points file available in flutter.

The "flutter build apk/aot" command accepts all three modes (--debug,
--profile, --release). This implies we need the entry_points_json_files
target also in "debug" mode (currently the build fails with an exception).

Maybe this should be fixed if flutter tools instead.

[mkustermann]

This seems to be decided. @cbracken just landed flutter/flutter@231b942 which will disallow debug builds in AOT (not just on iOS but also on Android now).

So then I can close this PR and the effort of changing the flutter tools aot building code.

[cbracken]

Context on flutter/flutter@231b942 is that we previously had a huge set of potential build type/option combinations and almost all of them are untested (both unit tests and integration tests) and/or very rarely used, but still incur maintenance overhead.

If there are legitimate use-cases for some of the code paths that I've been killing off, definitely shout and we can add them back with tests to ensure they stay healthy.