[Fix][Profiles] Do not update ProfileThemeColors for web apps

When a web app is installed, this is recognized as a theme change.
This web app has its own color provider which can be different from
that of the profile. This CL makes sure that that profile's colors are
not updated with the web app's color provider.

Bug: b:358060859

Change-Id: I454f488ca906b42f2560c0f3966c43ed0a83f4ca
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5766689
Reviewed-by: Ryan Sultanem <rsult@google.com>
Code-Coverage: findit-for-me@appspot.gserviceaccount.com <findit-for-me@appspot.gserviceaccount.com>
Reviewed-by: Alex Ilin <alexilin@chromium.org>
Commit-Queue: Amelie Schneider <amelies@google.com>
Cr-Commit-Position: refs/heads/main@{#1338516}