[COIL] Change chromium code search type links to use main rather than…

… master for extensions

    See this doc: go/chromium-coil-change for more info
    BUG=1210385

Change-Id: If5e4045785ac199f2018e166bb18d9b0812fefb6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2902905
Commit-Queue: John Palmer <jopalmer@chromium.org>
Commit-Queue: Ben Wells <benwells@chromium.org>
Auto-Submit: John Palmer <jopalmer@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Cr-Commit-Position: refs/heads/master@{#884334}

extensions/common/api/networking_onc.idl

@@ -9,7 +9,7 @@
 // </p>
 // <p>
 //   Network connection configurations are specified following
-//   <a href="https://chromium.googlesource.com/chromium/src/+/master/components/onc/docs/onc_spec.md">
+//   <a href="https://chromium.googlesource.com/chromium/src/+/main/components/onc/docs/onc_spec.md">
 //   Open Network Configuration (ONC)</a> specification.
 // </p>
 // <p>

extensions/docs/permissions.md

@@ -26,7 +26,7 @@ multiple hosts, so a single pattern may provide access to many different domains
 (or even, every domain).  For more information, see the public
 [match pattern documentation](https://developer.chrome.com/extensions/match_patterns).
 In the codebase, match patterns are implemented as
-[URLPattern](https://chromium.googlesource.com/chromium/src/+/master/extensions/common/url_pattern.h).
+[URLPattern](https://chromium.googlesource.com/chromium/src/+/main/extensions/common/url_pattern.h).
 
 #### Explicit Hosts
 Explicit host permissions are match patterns specified in the `permissions` key