Remove download resumption feature flag.

content/public/common/content_features.cc

Index: content/public/common/content_features.cc
diff --git a/content/public/common/content_features.cc b/content/public/common/content_features.cc
index b20ac77d1c9830a93bf4803c46fd42c52e068396..4f13922cf22665db3f4ac94381bc3e5f8e1584b3 100644
--- a/content/public/common/content_features.cc
+++ b/content/public/common/content_features.cc
@@ -28,11 +28,6 @@ const base::Feature kDefaultEnableGpuRasterization{
 const base::Feature kDoNotUnlockSharedBuffer{"DoNotUnlockSharedBuffer",
                                              base::FEATURE_DISABLED_BY_DEFAULT};
 
-// Downloads resumption will be controllable via a flag until it's enabled
-// permanently. See https://crbug.com/7648
-const base::Feature kDownloadResumption{"DownloadResumption",
-                                        base::FEATURE_ENABLED_BY_DEFAULT};
-
 // Speculatively pre-evaluate Javascript which will likely use document.write to
 // load an external script. The feature extracts the written markup and sends it
 // to the preload scanner.