preload-topchrome: add TopChromeWebUIConfig::ShouldAutoResizeHost()

`webui_resizes_host` controls if the WebUI content host view should
automatically resize to fit its content. It was only available in the
WebUIContentsWrapperT parameter list. This makes it difficult for the
preload manager to configure the WebContents ahead of creating the
wrapper.

This patch moves the parameter to
TopChromeWebUIConfig::ShouldAutoResizeHost() so that the preload manager
can read it for preloading.

This patch has no behavior change. The integration with the preload
manager will come in a follow up CL.

Bug: 339049707, 40168622
Low-Coverage-Reason: LARGE_SCALE_REFACTOR framework level change that touches previously uncovered WebUI (emoji_ui.cc)
Change-Id: If8dfa26a6553ef44cddd280ec4d652f4a61a5b80
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5713534
Reviewed-by: Thomas Lukaszewicz <tluk@chromium.org>
Reviewed-by: Erik Chen <erikchen@chromium.org>
Commit-Queue: Keren Zhu <kerenzhu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1329936}