MD Downloads: use "big search" box like MD history

chrome/browser/resources/md_downloads/manager.css

Index: chrome/browser/resources/md_downloads/manager.css
diff --git a/chrome/browser/resources/md_downloads/manager.css b/chrome/browser/resources/md_downloads/manager.css
index 89ff0acf022b678738941e10cf69e8717bed69ef..ffcec1d79416d7a27b4464d093a9a0b0fab9bdba 100644
--- a/chrome/browser/resources/md_downloads/manager.css
+++ b/chrome/browser/resources/md_downloads/manager.css
@@ -7,7 +7,6 @@
   flex: 1 0;
   flex-direction: column;
   height: 100%;
-  overflow-y: overlay;
 }
 
 @media screen and (max-width: 1024px) {
@@ -16,6 +15,12 @@
   }
 }
 
+#downloads-list {
+  /* TODO(dbeam): we're not setting scrollTarget explicitly, yet
+   * style="overflow: auto" is still being set by <iron-list>'s JS. Weird. */
+  overflow-y: overlay !important;
+}
+
 #no-downloads,
 #downloads-list {
   flex: 1;