[Devtools] Move palette switcher button back up to the top

Bug: 793225
Change-Id: I888f166d099b7829b942fc8d31c16fec8a3df411
Reviewed-on: https://chromium-review.googlesource.com/821950Reviewed-by: Pavel Feldman <pfeldman@chromium.org>
Commit-Queue: Alice Boxhall <aboxhall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523548}

third_party/WebKit/Source/devtools/front_end/color_picker/spectrum.css

@@ -473,7 +473,7 @@
 
 .spectrum-palette-switcher {
     right: 10px;
-    bottom: 9px;
+    top: 0;
     margin-top: 9px;
     position: absolute;
 }