Fix error when adding activities from Search Builder

[MegaphoneJon]

Overview

When you use the "Add Activity" task from Search Builder, you get an error on submitting the activity. Exact replication steps are on the issue: https://lab.civicrm.org/dev/core/issues/1323

Before

Yellow Screen of Death.

After

No error.

Technical Details

When you submit the activity, CiviCRM tries passing you back to the search screen you just came from. However, it doesn't handle Search Builder.

Comments

I'm tagging this as easy-review because of the simplicity of the steps to replicate, the limited scope of the class being altered, and the obvious correctness of the fix :)

[civibot]

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[alifrumin]

@eileenmcnaughton this looks ready to be merged to me!

• General standards

  • Explain (r-explain)
    • PASS : The goal/problem/solution have been adequately explained in the PR and the related gitlab ticket -> https://lab.civicrm.org/dev/core/issues/1323
  • User impact (r-user)
    • PASS: The change would be intuitive or unnoticeable for a majority of users who work with this feature.
  • Documentation (r-doc)
    • PASS: The changes do not require documentation.
  • Run it (r-run)
    • PASS: followed instructions in the overview on the jenkins build. Works as expected.

• Developer standards

  • Technical impact (r-tech)
    • PASS: The change preserves compatibility with existing callers/code/downstream.
  • Code quality (r-code)
    • PASS: The functionality, purpose, and style of the code seems clear+sensible.
  • Maintainability (r-maint)
    • PASS: The change sufficiently improves test coverage, or the change is trivial enough that it does not require tests.
  • Test results (r-test)
    • PASS: The test results are all-clear.

[eileenmcnaughton]

Thanks @MegaphoneJon & @alifrumin - looks good to me