It may look confusing to have parameters 'allowProtected' and 'checkModifiers' (it's not evident that the first one is ignored if the second one is 'false'), so replaced 'checkModifiers' was replaced by 'allowPrivateAndPackagePrivate'. The call sites were updated accordingly.

IDEA-CR-42161: IDEA-205502 Main appearance font is not used in several toolwindows and notifications on macOS

(cherry picked from commit 7a2156f1)

do not use default project to fix IDEA-194554 AE at com.intellij.codeInsight.documentation.DocumentationManager.assertSameProject

fix PsiTestUtil.removeContentEntry to remove the content entry with the given root, not just any entry containing it

Problem is that modal task doesn't mean that another modal task cannot be run in parallel.
As our tasks call invokeAndWait, some another UI events can be processed and as result, `closeProjectAndShowWelcomeFrameIfNoProjectOpened` will be called several times

Accordingly to JLS 8.8.9 default constructor is implicitly declared if there are no constructor declarations. If the superclass doesn't have an accessible no-arg constructor, it'll be a compile-time error which shouldn't bother those who tries to use the derived class.

This also fixes incorrect behavior when super-class declares package-private constructor (IDEA-208482).

Now it checks classes even if they don't have plugin.xml files in their modules, don't report error if an element and its class are declared in different modules included into the same plugin (IDEA-208472), show name of problematic class in error message, check serviceInterfaces attributes unless service is marked with 'overrides'.

for example, git-branches popup of IDEA-project has thousands of items