Revert "Hide the tool component if hidden set to true"

This reverts commit bcf0935f87d26bf08bb576c1124075e6ce730242.

Reason for revert: no longer needed after change 281898

Change-Id: I436a9bec9817afd7d13b45a2a8454b77cf76ad46

gr-image-diff-tool/gr-image-diff-tool_html.js

diff --git a/gr-image-diff-tool/gr-image-diff-tool_html.js b/gr-image-diff-tool/gr-image-diff-tool_html.js
index 212298c..887a028 100644
--- a/gr-image-diff-tool/gr-image-diff-tool_html.js
+++ b/gr-image-diff-tool/gr-image-diff-tool_html.js
@@ -22,12 +22,6 @@
     display: block;
     font-family: var(--font-family);
   }
-  /** This is needed as we have explicit display on :host
-    * which will override hidden from shared-styles
-    */
-  :host[hidden] {
-    display: none;
-  }
   #header {
     align-items: center;
     border-bottom: 1px solid var(--border-color, #ddd);