Minor fixes to C++ style guide.

Link to GN style guide fixed.

Added a link to the general C++ style guide from the C++11-specific page.

Text on both the C++ and C++11 pages updated to remove a reference to the wiki (presumably it's referrring to "this page") and instead say to make a CL when there is concensus.

Review-Url: https://codereview.chromium.org/2128723002
Cr-Commit-Position: refs/heads/master@{#404066}
diff --git a/styleguide/c++/c++.md b/styleguide/c++/c++.md
index 1b8e307b..e7af38be 100644
--- a/styleguide/c++/c++.md
+++ b/styleguide/c++/c++.md
@@ -11,9 +11,9 @@
 to automatically format C++ code. By policy, Clang's formatting of code should
 always be accepted in code reviews.
 
-You can propose changes to the style guide by sending an email to
-`[email protected]`. Ideally, the list will arrive at some consensus and the
-wiki page will be updated to mention that consensus. If there's no consensus,
+You can propose changes to this style guide by sending an email to
+`[email protected]`. Ideally, the list will arrive at some consensus and you can
+request review for a change to this file. If there's no consensus,
 `src/styleguide/c++/OWNERS` get to decide.
 
 Blink code in `third_party/WebKit` uses [Blink