Pass JavaRef to WebContents::FromJavaWebContents.

chrome/browser/android/tab_android.h

Index: chrome/browser/android/tab_android.h
diff --git a/chrome/browser/android/tab_android.h b/chrome/browser/android/tab_android.h
index 766c43848caa5804fba5152b79b28918a74b0485..544cb21f819a16df26a97354ab768a7b5e27518b 100644
--- a/chrome/browser/android/tab_android.h
+++ b/chrome/browser/android/tab_android.h
@@ -11,6 +11,7 @@
 #include <memory>
 
 #include "base/android/jni_weak_ref.h"
+#include "base/android/scoped_java_ref.h"
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/strings/string16.h"
@@ -83,12 +84,13 @@ class TabAndroid : public CoreTabHelperDelegate,
 
   // Returns the native TabAndroid stored in the Java Tab represented by
   // |obj|.
-  static TabAndroid* GetNativeTab(JNIEnv* env, jobject obj);
+  static TabAndroid* GetNativeTab(JNIEnv* env,
+                                  const base::android::JavaRef<jobject>& obj);
 
   // Function to attach helpers to the contentView.
   static void AttachTabHelpers(content::WebContents* web_contents);
 
-  TabAndroid(JNIEnv* env, jobject obj);
+  TabAndroid(JNIEnv* env, const base::android::JavaRef<jobject>& obj);
   ~TabAndroid() override;
 
   base::android::ScopedJavaLocalRef<jobject> GetJavaObject();