Fix highlighting for problems with incomplete finalLocation

Summary: This patch fixes highlighting for problems, which has incomplete finalLocation. Many checkers produce only line number in the log, which makes impossible to set correct range for problem without parsing of checked source file. To fix this case we adds LocationRangeMode methods which allows to control highlighting process for such problems.

Test Plan:
Tested on master branch with kdev-cppcheck plugin.

Results (line 63):

Original (old) behavior, ugly 1-symbol highlighting

New (improved behavior, with TrimmedLine mode

Reviewers: KDevelop

Subscribers: kdevelop-devel

Differential Revision: https://phabricator.kde.org/D3196