[clang] Fix issue introduced in predefined expressions in lambdas (#217021)
Resolves #213420.
The problem introduced in #211811 is that the search for the
`LambdaScopeInfo` corresponding to the current lambda operator stops at
the first scope info that is not a `CapturingScopeInfo`.
This is relevant in `getCurLambda` (where I looked when implementing the
PR), but not here.