Make touch-based synthetic gesture take touch slop into account.

content/browser/android/content_view_core_impl.cc

Index: content/browser/android/content_view_core_impl.cc
diff --git a/content/browser/android/content_view_core_impl.cc b/content/browser/android/content_view_core_impl.cc
index 2a53563c4f309e698c4ece2b021b230e0d2537cd..66f05aff0598eaf4e245f3d2aabb6f04ff2ea4f0 100644
--- a/content/browser/android/content_view_core_impl.cc
+++ b/content/browser/android/content_view_core_impl.cc
@@ -155,6 +155,14 @@ ContentViewCore* ContentViewCore::GetNativeContentViewCore(JNIEnv* env,
       Java_ContentViewCore_getNativeContentViewCore(env, obj));
 }
 
+float ContentViewCoreImpl::GetDeviceScaleFactor() const {
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
+  if (obj.is_null())
+    return 1.0f;
+  return Java_ContentViewCore_getDeviceScaleFactor(env, obj.obj());
+}
+
 ContentViewCoreImpl::ContentViewCoreImpl(JNIEnv* env, jobject obj,
                                          bool hardware_accelerated,
                                          WebContents* web_contents,