Reland "Correct ParagraphBuilder::getText() behavior"

This reverts commit 632437b9c93f64876f0594f61681e353b665805c.

Reason for revert: Fixing the build

Original change's description:
> Revert "Correct ParagraphBuilder::getText() behavior"
>
> This reverts commit fce12076322a30ec5afb36257d7f0288786b033f.
>
> Reason for revert: Build break (and merge problem)
>
> Original change's description:
> > Correct ParagraphBuilder::getText() behavior
> >
> > And make sure that no text modifications could be done
> > after ParagraphBuilder::Build() until Reset()
> >
> > Change-Id: I5e7b2a99fb4577ddd41e23d153783642d606aaef
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/618518
> > Reviewed-by: Julia Lavrova <jlavrova@google.com>
> > Reviewed-by: Ben Wagner <bungeman@google.com>
> > Commit-Queue: Julia Lavrova <jlavrova@google.com>
>
> Change-Id: If3bb583fb0d05ba0ab3fb8fc58c7632fe32d68fc
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/631836
> Commit-Queue: Julia Lavrova <jlavrova@google.com>
> Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>

Change-Id: I5e4862fa92a1acec364a844ec3c5fe01d772ddd0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/632276
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Julia Lavrova <jlavrova@google.com>
2 files changed