show preview during DnD of classes; avoid custom refactorings run (IDEA-133079)
method call type: erasure should not be applied if method doesn't have type params; < 1.8 (IDEA-132810)
[git] IDEA-133309 Fix possible NPE

Although the setter is @NotNull and default value is not null,
myUpdateMethod can still receive a null due to our serialization
engine problems => protect against this by reusing default value.
[git] IDEA-133368 Enable git add on new files

Until we know about the index (and therefore know if the file is
added+unstaged-modified) it's better to allow the action than to
disable it.
[log] IDEA-116400 Cut the compound commit list after multi-repo join