Since almost all Google domains support HTTPS, and it is a good practice to
use HTTPS wherever possible, thus in this patch, I changed most HTTP links
to https whose domains are known to support HTTPS well.

Modifications are generated by running these commands in src/docs directory:
sed -i 's/http:\/\/www.chromium.org/https:\/\/www.chromium.org/g' *.md
sed -i 's/http:\/\/developer.android.com/https:\/\/developer.android.com/g' *.md
sed -i 's/http:\/\/dev.chromium.org/https:\/\/dev.chromium.org/g' *.md
sed -i 's/http:\/\/build.chromium.org/https:\/\/build.chromium.org/g' *.md
sed -i 's/http:\/\/src.chromium.org/https:\/\/src.chromium.org/g' *.md
sed -i 's/http:\/\/crbug.com/https:\/\/crbug.com/g' *.md
sed -i 's/http:\/\/groups.google.com/https:\/\/groups.google.com/g' *.md
sed -i 's/http:\/\/cs.chromium.org/https:\/\/cs.chromium.org/g' *.md
sed -i 's/http:\/\/codereview.chromium.org/https:\/\/codereview.chromium.org/g' *.md

BUG=

Review-Url: https://codereview.chromium.org/2545363002
Cr-Commit-Position: refs/heads/master@{#436501}