Moved Cronet code under Connectivity

$ cp -r Cronet/ Connectivity/
$ rm -r Cronet/*

Bug: 251054736
Test: atest CronetApiTest
Change-Id: Id78e239596402dc788b3cac7b8ca3de4aad795d2
34 files changed
tree: 4b825dc642cb6eb9a060e54bf8d69288fbee4904

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