doc: Fix typo in MakeStrongBinding() section

mojo/public/cpp/bindings/README.md

 # Mojo C++ Bindings API
 This document is a subset of the [Mojo documentation](/mojo).
 
 [TOC]
 
 ## Overview
 The Mojo C++ Bindings API leverages the
 [C++ System API](/mojo/public/cpp/system) to provide a more natural set of
 primitives for communicating over Mojo message pipes. Combined with generated
 code from the [Mojom IDL and bindings generator](/mojo/public/tools/bindings),
@@ skipping 831 matching lines @@
   // sample::mojom::Logger:
   void Log(const std::string& message) override {
     LOG(ERROR) << "[Logger] " << message;
   }
 
  private:
   // NOTE: This doesn't own any Binding object!
 };
 
 db::mojom::LoggerPtr logger;
-mojo::MakeStrongBinding(base::MakeUnique<DatabaseImpl>(),
+mojo::MakeStrongBinding(base::MakeUnique<LoggerImpl>(),
                         mojo::MakeRequest(&logger));
 
 logger->Log("NOM NOM NOM MESSAGES");
 ```
 
 Now as long as `logger` remains open somewhere in the system, the bound
-`DatabaseImpl` on the other end will remain alive.
+`LoggerImpl` on the other end will remain alive.
 
 ### Binding Sets
 
 Sometimes it's useful to share a single implementation instance with multiple
 clients. [**`BindingSet`**](https://cs.chromium.org/chromium/src/mojo/public/cpp/bindings/binding_set.h)
 makes this easy. Consider the Mojom:
 
 ``` cpp
 module system.mojom;
 
@@ skipping 561 matching lines @@
 
 ```cpp
 inline bool IsKnownEnumValue(Department value);
 ```
 
 ### Additional Documentation
 
 [Calling Mojo From Blink](https://www.chromium.org/developers/design-documents/mojo/calling-mojo-from-blink)
 :    A brief overview of what it looks like to use Mojom C++ bindings from
      within Blink code.