Upgrade from Chromium 126.0.6478.17 to Chromium 126.0.6478.26

[cdesouza-chromium]

Resolves brave/brave-browser#38675

Submitter Checklist:

• I confirm that no security/privacy review is needed and no other type of reviews are needed, or that I have requested them
• There is a ticket for my issue
• Used Github auto-closing keywords in the PR description above
• Wrote a good PR/commit description
• Squashed any review feedback or "fixup" commits before merge, so that history is a record of what happened in the repo, not your PR
• Added appropriate labels (QA/Yes or QA/No; release-notes/include or release-notes/exclude; OS/...) to the associated issue
• Checked the PR locally:
  • npm run test -- brave_browser_tests, npm run test -- brave_unit_tests wiki
  • npm run presubmit wiki, npm run gn_check, npm run tslint
• Ran git rebase master (if needed)

Reviewer Checklist:

• A security review is not needed, or a link to one is included in the PR description
• New files have MPL-2.0 license header
• Adequate test coverage exists to prevent regressions
• Major classes, functions and non-trivial code blocks are well-commented
• Changes in component dependencies are properly reflected in gn
• Code follows the style guide
• Test plan is specified in PR before merging

After-merge Checklist:

• The associated issue milestone is set to the smallest version that the
  changes has landed on
• All relevant documentation has been updated, for instance:
  • https://github.com/brave/brave-browser/wiki/Deviations-from-Chromium-(features-we-disable-or-remove)
  • https://github.com/brave/brave-browser/wiki/Proxy-redirected-URLs
  • https://github.com/brave/brave-browser/wiki/Fingerprinting-Protections
  • https://github.com/brave/brave-browser/wiki/Brave%E2%80%99s-Use-of-Referral-Codes
  • https://github.com/brave/brave-browser/wiki/Web-Compatibility-Exceptions-in-Brave
  • https://github.com/brave/brave-browser/wiki/QA-Guide
  • https://github.com/brave/brave-browser/wiki/P3A

Test Plan:

[github-actions]

[puLL-Merge] - brave/brave-core@23896

Description

This pull request makes various changes across the Chromium codebase. The main motivation seems to be to add Brave-specific functionality and preferences.

Changes

Changes

• app/extensions_strings.grdp, app/extensions_strings_override.grdp, app/generated_resources.grd:
  • Adds new message strings related to extensions deprecation, Google Lens, and profile reporting
• chrome/browser/BUILD.gn, chrome/browser/about_flags.cc, chrome/browser/prefs/browser_prefs.cc, chrome/browser/ui/BUILD.gn, chrome/browser/ui/browser.cc, chrome/browser/ui/views/location_bar/location_bar_view.cc, chrome/browser/ui/views/permissions/permission_prompt_bubble_base_view.cc, chrome/browser/ui/webui/extensions/extensions_ui.cc, chrome/test/BUILD.gn:
  • Adds Brave-specific build flags, About flags entries, preference registrations, and UI customizations
• chrome/browser/renderer_context_menu/render_view_context_menu.cc, chrome/browser/resources/extensions/item_list.html, chrome/browser/resources/extensions/item_list.ts:
  • Modifies extension context menu and item list UI
• components/sync/protocol/proto_visitors.h, components/sync/service/BUILD.gn, components/sync/service/sync_service_impl.h:
  • Adds support for Brave Sync
• content/browser/browser_main_runner_impl.cc, content/browser/renderer_host/navigation_controller_impl.cc, content/browser/renderer_host/navigation_request.cc:
  • Injects Brave-specific functionality into content layer
• ios/chrome/browser/shared/model/prefs/browser_prefs.mm:
  • Registers Brave-specific preferences on iOS
• services/network/public/cpp/BUILD.gn:
  • Adds a Brave-specific build flag
• third_party/blink/renderer/platform/runtime_enabled_features.json5:
  • Enables a Brave-specific runtime feature flag
• package.json:
  • Bumps Chromium version to 126.0.6478.26

Overall, this PR adds a significant amount of Brave customizations across different layers of the Chromium codebase.

[github-actions]

The following commits were not verified:
5dfe1d6 (unsigned)
9b55d76 (unsigned)
56884a9 (unsigned)
4fc0390 (unsigned)

[kjozwiak]

LGTM 👍