[Canary] Revert "Add 64-bit primary targets for standalone Stable WebView"

This reverts commit e139245a203fd3b4f4b2e68525b4ab3de020ec89.

Reason for revert: tentatively reverting as this seems to be the cause of build failures in android-arm64. Additional details in bug

Sample failure: https://ci.chromium.org/ui/p/chrome/builders/ci/android-arm64/37016/overview

Bug: 431718133
Original change's description:
> Add 64-bit primary targets for standalone Stable WebView
>
> Add is_64_bit_browser variable to all standalone targets.
>
> Extend standalone version code to consider the is_64_bit_browser
> variable and high-end arm64 builds.
>
> Only set the force_32_bit manifest if is_64_bit_browser is not set.
>
> Before this change standalone WebView will run a 32-bit renderer even
> if is_64_bit_browser is set to true.
>
> Changes related to other release channels will be part of
> crbug.com/431722474
>
> Bug: 431718133
> Change-Id: I46cf8d9571176535ae867ef340a5bdd69bbf64dd
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6760879
> Reviewed-by: Sam Maier <[email protected]>
> Reviewed-by: Richard (Torne) Coles <[email protected]>
> Commit-Queue: Ziad Youssef <[email protected]>
> Cr-Commit-Position: refs/heads/main@{#1492713}

(cherry picked from commit 66183f643497a2f131c2ff5a9255fcf8493c42dc)

Bug: 431718133
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Change-Id: Id82a6e17b0d9443c7e8d414d12af2de424dbd511
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6787224
Reviewed-by: Richard (Torne) Coles <[email protected]>
Owners-Override: Liza Bipin <[email protected]>
Commit-Queue: Liza Bipin <[email protected]>
Cr-Original-Commit-Position: refs/heads/main@{#1492796}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6793828
Reviewed-by: Krishna Govind <[email protected]>
Owners-Override: Krishna Govind <[email protected]>
Bot-Commit: Rubber Stamper <[email protected]>
Cr-Commit-Position: refs/branch-heads/7324@{#4}
Cr-Branched-From: d496557e4fbca10db01a5aaf6da8790f012f3157-refs/heads/main@{#1492762}

• android_webview/BUILD.gn[diff]
• android_webview/expectations/system_webview_64_32_bundle.AndroidManifest.expected[Deleted - diff]
• android_webview/system_webview_apk_tmpl.gni[diff]
• build/util/android_chrome_version.py[diff]
• chrome/android/BUILD.gn[diff]
• chrome/version.gni[diff]