This CL changes the FieldAccessExpression to include a SourcePosition
for the field, allowing a jump from such an access to the definition
of a field inside a class or struct.

Drive-by: Change the source position of a field from the position
of its type to the position of its name. This will coincidentally
improve the accuracy of error messages.

R=danno@chromium.org

Bug: v8:8880
Change-Id: I7996e8a57a2ff90e8bdca6f40c1b298d48071e23
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1512573Reviewed-by: Daniel Clifford <danno@chromium.org>
Commit-Queue: Simon Zünd <szuend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60162}