WebEngine workshop patches

• f86cfe8202c Declare a Qt IPC message class

squash:

• daf98e6cbce <chromium> BrowserAccessibilityManager::Create is implemented in Qt sources.
• 54c2ac93fe4 Remove the Running without SUID sandbox error message
• 15effe90f54 Use target sysroot only with target toolchain
• 12aff07d7be Do not force the use of Google's custom clang binaries
• 404029dfe83 Do not directly override libc symbols from the library.
• bd50a066e2a Remove reference to safe_browsing constants
• 26b797c757b Fix Renderer and GPU threads on windows
• 445060bb2e9 Fix race condition on gpu thread initialization
• 484729568cc Fix --single-process --disable-gpu combination not to hit asserts
• 60e0793e245 Fix QRC cookies for tests with network-service
• 404029dfe83 Do not directly override libc symbols from the library.
• e5b29bc096c Fix recursive deadlock in sandbox::InitLibcLocaltimeFunctions

upstream:

• 15c2004e2e9 Suppress error message on unneeded V8 external startup files
• f785a68cedf Fix incorrect dependency on shim headers
• 2621e3c2875 Allow shims in official builds
• e976a178ab2 Support linux-clang-libc++ builds
• 862f78190ea Unbundle Linux system libraries for GN
• be4cd754e6f Optionally link with system ffmpeg
• 97c9f8d0b71 Optionally link with system ICU
• eeccfe807ae Improve jpeg headers handling
• e936e9c5211 Fix headers for libpng in skia
• 4cfda813c3a Allow Service Workers without HTTP headers (again)
• dd722c7c9f1 Do not build swiftshader when it is disabled
• d9df77e2f1a Fix hanging of process when application is closed too fast
• d3d28254cc3 Pass original_request_url correctly (for view-source tests)
• ccd54fe5f0e Enable high resolution printing
• 222f3bf5b26 Legalize the bloody code
• e96095db5e7 Reintroduce SANDBOX_EXPORTS, and fix it for heterogeneous executables
• 6dc94729f2a Fix zygote path used
• 81e74140320 Fix changing should_override_user_agent_in_new_tabs_
• eea17e6a064 Do not override ios settings

check if meaningful or fixed:

• 107cbd2ebaa Fix webfonts with wrong hinting on Linux
• 180246344e5 Fix override of malloc
• 26b797c757b Fix Renderer and GPU threads on windows
• 73030c7da5b Invalidate cached selection bounds on scrolling
• 8d2d8548437 Enable NativeThemeAura on macOS too
• 75d0dad64c8 Make text selection handles available on macOS too
• 8eced4eb145 [Revert] Hook up new rc.py.
• 5e883407074 Disable responsiveness watcher
• 1681802beb6 Fix CDM on OSX and Windows with component installer
• 039557e5aa9 Enable the option to remove previous user PrefService

split:

• bec44cc7101 Qt GN integration
• 0dc3904c28d Fix printing sources for Qt and add them to the build. (display change, update toolkit_qt)
• Consider constexpr fixes patch
• 4366322b162 Use ui::Compositor (3rdparty) (remove what isnt needed)

regroup

• 1209cf45261 Optionally unbundle libvpx, opus, FLAC, re2 and OpenH264
• 862f78190ea Unbundle Linux system libraries for GN
• eeccfe807ae Improve jpeg headers handling

fix

• bd503db5998 Fix Chrome resources and WebUI we need

rename

• 3ba38cdff2a Fix building without WebSpeech (and squash with soda patch)