[WebView] Disallow geolocation on insecure origins for apps targeting N and higher.

Merge to M51.

In Chrome geolocation has been disabled on insecure origins
previously in crrev.com/1485973002.

For WebView we are enabling same behavior for apps that are
targeting N and higher versions of Android. This is to allow
for a smooth transition and remain reasonably backwards
compatible with older apps.

BUG=603574
TBR=torne@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review URL: https://codereview.chromium.org/1882783002

Cr-Commit-Position: refs/heads/master@{#387299}
(cherry picked from commit 4f4086735aeb59b937e8216c923f0ea7c58a3602)

Review URL: https://codereview.chromium.org/1894563002

Cr-Commit-Position: refs/branch-heads/2704@{#75}
Cr-Branched-From: 6e53600def8f60d8c632fadc70d7c1939ccea347-refs/heads/master@{#386251}
7 files changed