Merge pull request #2557 from ian-r-rose/full_size_iframe

Make IFrames take up the whole space available.

packages/apputils/style/iframe.css

@@ -2,6 +2,12 @@
 | Copyright (c) Jupyter Development Team.
 | Distributed under the terms of the Modified BSD License.
 |----------------------------------------------------------------------------*/
+
+.jp-IFrame {
+  width: 100%;
+  height: 100%;
+}
+
 /*
 When drag events occur, `p-mod-override-cursor` is added to the body.
 Because iframes steal all cursor events, the following two rules are necessary
@@ -12,7 +18,6 @@ body.p-mod-override-cursor .jp-IFrame {
   position: relative;
 }
 
-
 body.p-mod-override-cursor .jp-IFrame:before {
   content: '';
   position: absolute;