In response to a non-identifier token after a dot, DSLParser would
attempt to swizzle a zero-length field and fail an assertion.
The same basic code path exists in the old compiler, but the resulting
parse error causes the process to abort before it attempts to process
the zero-length swizzle.
Bug: oss-fuzz:38106
Change-Id: Ifd997ce1d564b5f6ef0a9a785d8d9e254785e600
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/446185
Reviewed-by: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
