Need ability to set fixed ID property for cdk-overlay-pane

[thiagopg84]

Issue type

I'm submitting a ... (check one with "x")

• [ ] bug report
• [X] feature request

Issue description

Current behavior: Currently, the cdk-overlay-pane container has a dynamic ID ('#cdk-overlay-' + number of modals that have been opened). Each time a new modal is opened, the number is incremented (#cdk-overlay-1, #cdk-overlay-2 etc).

Expected behavior: For testing purposes, to have the ability to set a fixed ID or to halt the ID counter. Since the modal is destroyed and removed from the DOM after it closes, maybe it wouldn't be a problem to use the same ID.

Steps to reproduce:

Related code:

Other information:

npm, node, OS, Browser

Angular, Nebular