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[x] feature request
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Current behavior
It is not possible to customize which URLs are considered safe.

Expected behavior
A user could customize the REGEX used to match safe urls.

Minimal reproduction of the problem with instructions
N/A

What is the motivation / use case for changing the behavior?
When you are using ionic 2, Android will usually return URLs that begin with content://. Then you have to explicitly call bypassSecurityTrustUrl to be able to show them. In Angular 1 you could customize this by injecting $compileProvider and calling: $compileProvider.imgSrcSanitizationWhitelist(/^\s*(https?|ftp|file|blob|content):|data:image\//);. But there's no convenience alternative for angular 2.

Please tell us about your environment:
N/A

• Angular version: 2.0.X
  2.2.0-rc.0

• Browser: all

• Language: all

• Node (for AoT issues): node --version = 7.1.0