*DRAFT* Move MediaDeviceIDSalt from chrome/ to components/ and use it in Android WebView.

android_webview/browser/aw_resource_context.h

Index: android_webview/browser/aw_resource_context.h
diff --git a/android_webview/browser/aw_resource_context.h b/android_webview/browser/aw_resource_context.h
index 20857c728d0488b275372e0e4cebdbb5e934b311..3e56730589cced3ef3c3a9e7c270661e625c7a0b 100644
--- a/android_webview/browser/aw_resource_context.h
+++ b/android_webview/browser/aw_resource_context.h
@@ -12,15 +12,23 @@
 #include "base/synchronization/lock.h"
 #include "content/public/browser/resource_context.h"
 
+class PrefService;
+
 namespace net {
 class URLRequestContextGetter;
 }
 
+namespace media_device_id_salt {
+class MediaDeviceIDSalt;
+}
+
 namespace android_webview {
 
 class AwResourceContext : public content::ResourceContext {
  public:
-  explicit AwResourceContext(net::URLRequestContextGetter* getter);
+  AwResourceContext(net::URLRequestContextGetter* getter,
+                    PrefService* pref_service,
+                    bool incognito);
   ~AwResourceContext() override;
 
   void SetExtraHeaders(const GURL& url, const std::string& headers);
@@ -29,12 +37,14 @@ class AwResourceContext : public content::ResourceContext {
   // content::ResourceContext implementation.
   net::HostResolver* GetHostResolver() override;
   net::URLRequestContext* GetRequestContext() override;
+  SaltCallback GetMediaDeviceIDSalt() override;
 
  private:
   net::URLRequestContextGetter* getter_;
 
   base::Lock extra_headers_lock_;
   std::map<std::string, std::string> extra_headers_;
+  scoped_refptr<media_device_id_salt::MediaDeviceIDSalt> media_device_id_salt_;
 
   DISALLOW_COPY_AND_ASSIGN(AwResourceContext);
 };