Fix hermes chrome debugger for Flipper

Summary: When Flipper upgraded Electron it broke the iframe sandboxing for devtools, the fix is to use a webview (which requires some CSS fixes to render full screen).

Reviewed By: ArchDev

Differential Revision: D19446243

fbshipit-source-id: 7fd0b0fc922aa6c05c24efc20adce1cb61f24c99

static/icons.json

@@ -50,7 +50,8 @@
     16
   ],
   "caution-octagon": [
-    16
+    16,
+    20
   ],
   "caution-triangle": [
     12,
@@ -184,7 +185,8 @@
     16
   ],
   "question-circle": [
-    12
+    12,
+    20
   ],
   "question": [
     16
@@ -321,5 +323,8 @@
   ],
   "pencil-outline": [
     16
+  ],
+  "code": [
+    12
   ]
 }