Add enhanced filters to Network panel.

Source/devtools/front_end/filter.css

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 .filter-text-filter {
     display: flex;
     margin-left: 1px;
     margin-right: 1px;
-    flex: 0 0 100px;
+    flex: 1 0 100px;
 }
 
 .filter-text-filter.supports-regex {
     flex: 0 0 155px;
 }
 
 .filter-text-filter label {
     margin: auto 0;
 }
 
@@ skipping 95 matching lines @@
     -webkit-mask-position: -32px -48px;
 }
 
 .filters-toggle.toggled-shown .glyph {
     background-color: rgb(66, 129, 235);
 }
 
 .filters-toggle.toggled-active .glyph {
     background-color: rgb(216, 0, 0);
 }