lldb: don't issue command when there's no env variables to set, fix Bug 391897

Authored by qi437103 on Mar 20 2018, 6:39 PM.

Description

lldb: don't issue command when there's no env variables to set, fix Bug 391897

Summary:
LLDB becomes stricter about the settings set target.env-vars
command. Now it doens't allow empty arguments. This causes a warning
when start debugging session in KDevelop.

https://bugs.kde.org/show_bug.cgi?id=391897

Test Plan:

  • Created a new project with an empty environment variable profile
  • Start debugging with lldb
  • No warnings

Reviewers: apol, KDevelop

Reviewed By: apol, KDevelop

Subscribers: kdevelop-devel

Differential Revision: https://phabricator.kde.org/D11524

(cherry picked from commit 3fd20921df6a9d69c54bfc1add86f42185652148)