[clang-tools-extra] [clang-doc] Add a breadcrumb navigation bar (PR #173297)

[Paul Kirth via cfe-commits]

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@@ -12,5 +12,12 @@
                 </li>
             </ul>
         </div>
+        {{#HasContexts}}
+        <div class="navbar-breadcrumb-container">
+            {{#Contexts}}
+            <div class="navbar-breadcrumb-item"><a href="{{RelativePath}}{{DocumentationFileName}}.html">{{Name}}</a></div>{{^End}}→{{/End}}
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ilovepi wrote:

`::` also sounds better to me. 

https://github.com/llvm/llvm-project/pull/173297