Fix \t vs \s errors in webui_explainer.md

docs/webui_explainer.md

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@@ skipping 100 matching lines @@
 return nullptr;  // Not a known host; no special access.
 ```
 
 and if a factory knows how to handle a host (returns a `WebUIFactoryFunction`),
 the navigation machinery [grants the renderer process WebUI
 bindings](#bindings) via the child security policy.
 
 ```c++
 // RenderFrameHostImpl::AllowBindings():
 if (bindings_flags & BINDINGS_POLICY_WEB_UI) {
-        ChildProcessSecurityPolicyImpl::GetInstance()->GrantWebUIBindings(
-                        GetProcess()->GetID());
+  ChildProcessSecurityPolicyImpl::GetInstance()->GrantWebUIBindings(
+      GetProcess()->GetID());
 }
 ```
 
 The factory creates a [`WebUIController`](#WebUIController) for a tab.
 Here's an example:
 
 ```c++
 // Controller for chrome://donuts.
 class DonutsUI : public content::WebUIController {
  public:
@@ skipping 309 matching lines @@
 }
 ```
 
 This method is basically just a
 [`CallJavascriptFunction()`](#CallJavascriptFunction) wrapper that calls a
 global "cr.webUIResponse" method with a success value of false.
 
 ```c++
 // WebUIMessageHandler::RejectJavascriptCallback():
 CallJavascriptFunction("cr.webUIResponse", callback_id, base::Value(false),
-                                                                                         response);
+                       response);
 ```
 
 See also: [`ResolveJavascriptCallback`](#ResolveJavascriptCallback)
 
 <a name="ResolveJavascriptCallback"></a>
 ### WebUIMessageHandler::ResolveJavascriptCallback()
 
 This method is called in response to
 [`cr.sendWithPromise()`](#cr_sendWithPromise) to fulfill an issued Promise,
 often with a value. This results in runnings any fulfillment (first) callbacks
@@ skipping 33 matching lines @@
 if (enabled_bindings_ & BINDINGS_POLICY_WEB_UI)
   WebUIExtension::Install(frame_);
 ```
 
 If the bindings exist, a global `chrome.send()` function is exposed to the
 renderer:
 
 ```c++
 // WebUIExtension::Install():
 v8::Local<v8::Object> chrome =
-                GetOrCreateChromeObject(isolate, context->Global());
+    GetOrCreateChromeObject(isolate, context->Global());
 chrome->Set(gin::StringToSymbol(isolate, "send"),
-                                                gin::CreateFunctionTemplate(
-                                                                isolate, base::Bind(&WebUIExtension::Send))->GetFunction());
+            gin::CreateFunctionTemplate(
+                isolate, base::Bind(&WebUIExtension::Send))->GetFunction());
 ```
 
 The `chrome.send()` method takes a message name and argument list.
 
 ```js
 chrome.send('messageName', [arg1, arg2, ...]);
 ```
 
 The message name and argument list are serialized to JSON and sent via the
 `ViewHostMsg_WebUISend` IPC message from the renderer to the browser.
 
 ```c++
 // In the renderer (WebUIExtension::Send()):
 render_view->Send(new ViewHostMsg_WebUISend(render_view->GetRoutingID(),
-                                                                                                                                                                                frame->GetDocument().Url(),
-                                                                                                                                                                                message, *content));
+                                            frame->GetDocument().Url(),
+                                            message, *content));
 ```
 ```c++
 // In the browser (WebUIImpl::OnMessageReceived()):
 IPC_MESSAGE_HANDLER(ViewHostMsg_WebUISend, OnWebUISend)
 ```
 
 The browser-side code does a map lookup for the message name and calls the found
 callback with the deserialized arguments:
 
 ```c++
@@ skipping 131 matching lines @@
 let localLinks = Array.from(document.querySelectorAll('a[href^="#"]'));
 let hrefs = localLinks.map(a => a.href.split('#')[1]);
 
 hrefs.forEach(href => {
   if (names.includes(href))
     console.info('found: ' + href);
   else
     console.error('broken href: ' + href);
 })
 </script>