Update to Chromium version 82.0.4085.0 (#749737)

- Building on macOS now requires the 10.15 SDK. Xcode 11.3 is recommended as
  Xcode 11.4 is not currently supported (see https://crbug.com/1065146).
- Jumbo build configuration is no longer supported.

Chromium is skipping the M82 release and consequently no CEF 4085 branch will
be created. For details on the Chromium decision see
https://groups.google.com/a/chromium.org/d/msg/chromium-dev/Vn7uzglqLz0/JItlSrZxBAAJ

libcef/common/values_impl.cc

@@ -378,7 +378,7 @@ CefValueController* CefValueImpl::GetValueController() const {
   return nullptr;
 }
 
-void CefValueImpl::AcquireLock() {
+void CefValueImpl::AcquireLock() NO_THREAD_SAFETY_ANALYSIS {
   lock_.Acquire();
 
   CefValueController* controller = GetValueController();
@@ -386,7 +386,7 @@ void CefValueImpl::AcquireLock() {
     controller->lock();
 }
 
-void CefValueImpl::ReleaseLock() {
+void CefValueImpl::ReleaseLock() NO_THREAD_SAFETY_ANALYSIS {
   CefValueController* controller = GetValueController();
   if (controller) {
     controller->AssertLockAcquired();