Swap theme search to iframe search-frame page

[dmitrymatio]

Description

The theme will now iframe the search page at /search-frame/ like our Franklin pages do already.
This will point to the same search page once deployed site wide.
The search frame will communicate pathname to be mapped to assign local product filter as user moves around the site.

Additional bug fixes:

• indexPrefix undefined error on page load with query parameters
• undefined links when setting link.target while loading results
• aio-Search-close button missing error when testing on search-frame page

Related Issue

DEVSITE-646

Motivation and Context

Propagating upgrades to search is a major effort due to the decentralized nature of the current search architecture.
A more centralized approach will simplify the search maintenance and make the experience much more consistent site wide.

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have signed the Adobe Open Source CLA.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.