Use hasCondition() or hasSource() to confirm their existence
If the rule without condition or source is used, it causes the renderer
crash because the IDL expect condition() and source() is used only if
they are set.
Change-Id: I34b8f76b1cf4f245b7b096db120176134d72b6c8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5504213
Reviewed-by: Sam McNally sammc@chromium.org
Reviewed-by: Minoru Chikamune chikamune@chromium.org
Commit-Queue: Yoshisato Yanagisawa yyanagisawa@chromium.org
Cr-Commit-Position: refs/heads/main@{#1294810}