In Angular, it used to be an accepted practice to use strings as dependency
injection tokens. E.g. {provide: 'test', useValue: 'provided'}. However,
the Ivy node injection system did not support this. The Ivy DI system
attempts to patch a Bloom bit index onto each type registered with it, and
this patch operation does not work for a string token.
This commit adds string token support to the bloom filter system by
reserving bit 0 for string tokens. This eliminates the need for each string
token to store its own Bloom bit, at the expense of slightly more expensive
lookups of string tokens.
PR Close#27383
64a34616d8