The js_expected_symbol_test implementation extracts symbols names
from a rollup iife bundle. Previously, it only handled the case
with a simple 'var bundle = ...;' statement.
Sometimes, rollup produces a more complex bundle, where the 'bundle'
variable is not the only top-level variable declared in the same
declaration statement. This commit patches the symbol exctractor
to support this more complex case.
Additionally, when the symbol test fails, it prints a command to
accept the symbol diff. This command needs to include the
--define=compile flag to ensure the diff is applied in the same
compile mode as the test was run.
PR Close#24677
Using `-—define` causes bazel to bust the cache which means that doing
`bazel test target` followed by `bazel run -—define UPDATE_GOLDEN=1 target` will
cause caches to be invalidated and house full rebuild.
PR Close#22913
