Remove most native WebContents references from Java

android_webview/native/aw_settings.cc

Index: android_webview/native/aw_settings.cc
diff --git a/android_webview/native/aw_settings.cc b/android_webview/native/aw_settings.cc
index 43ea4aebe86f7c1e29254c1ecf4d28dcecbec4ba..6589e960b3c245a7cc348270c0ca982d352ca1d4 100644
--- a/android_webview/native/aw_settings.cc
+++ b/android_webview/native/aw_settings.cc
@@ -70,13 +70,14 @@ class AwSettingsUserData : public base::SupportsUserData::Data {
   AwSettings* settings_;
 };
 
-AwSettings::AwSettings(JNIEnv* env, jobject obj, jlong web_contents)
-    : WebContentsObserver(
-          reinterpret_cast<content::WebContents*>(web_contents)),
+AwSettings::AwSettings(JNIEnv* env,
+                       jobject obj,
+                       content::WebContents* web_contents)
+    : WebContentsObserver(web_contents),
       renderer_prefs_initialized_(false),
       aw_settings_(env, obj) {
-  reinterpret_cast<content::WebContents*>(web_contents)->
-      SetUserData(kAwSettingsUserDataKey, new AwSettingsUserData(this));
+  web_contents->SetUserData(kAwSettingsUserDataKey,
+                            new AwSettingsUserData(this));
 }
 
 AwSettings::~AwSettings() {
@@ -407,8 +408,10 @@ void AwSettings::PopulateWebPreferencesLocked(
 
 static jlong Init(JNIEnv* env,
                   jobject obj,
-                  jlong web_contents) {
-  AwSettings* settings = new AwSettings(env, obj, web_contents);
+                  jobject web_contents) {
+  content::WebContents* contents = content::WebContents::FromJavaWebContents(
+      web_contents);
+  AwSettings* settings = new AwSettings(env, obj, contents);
   return reinterpret_cast<intptr_t>(settings);
 }