DevTools: migrate DevTools APIs to use WebContents instead of RenderViewHost.

chrome/browser/extensions/api/debugger/debugger_api.cc

Index: chrome/browser/extensions/api/debugger/debugger_api.cc
diff --git a/chrome/browser/extensions/api/debugger/debugger_api.cc b/chrome/browser/extensions/api/debugger/debugger_api.cc
index 4e02a8df1abef9189b07cc9c3cf734022a081537..8fe17fb86787289a785b9ca59ac44edc246aa4f7 100644
--- a/chrome/browser/extensions/api/debugger/debugger_api.cc
+++ b/chrome/browser/extensions/api/debugger/debugger_api.cc
@@ -536,7 +536,7 @@ bool DebuggerFunction::InitAgentHost() {
         return false;
       }
       agent_host_ = DevToolsAgentHost::GetOrCreateFor(
-          extension_host->render_view_host());
+          extension_host->host_contents());
     }
   } else if (debuggee_.target_id) {
     agent_host_ = DevToolsAgentHost::GetForId(*debuggee_.target_id);