Fix Brave bookmark drag-and-drop

fix #10936

Test Plan:
1. go to about:bookmarks, try dragging and dropping some bookmarks. it should work.
2. drag a tab to change its position. it should work.

app/extensions.js

@@ -134,6 +134,20 @@ let generateBraveManifest = () => {
           getBraveExtUrl('about-blank.html'),
           getBraveExtUrl('about-blank.html') + '#*'
         ]
+      },
+      {
+        run_at: 'document_start',
+        all_frames: true,
+        js: [
+          'content/scripts/dndHandler.js'
+        ],
+        matches: [
+          '<all_urls>'
+        ],
+        exclude_globs: [
+          indexHTML,
+          getBraveExtUrl('*')
+        ]
       }
     ],
     web_accessible_resources: [

app/extensions/brave/content/scripts/dndHandler.js

@@ -0,0 +1,34 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+function hasBraveDragData (dataTransfer) {
+  if (!dataTransfer || !dataTransfer.types) {
+    return false
+  }
+  for (let i = 0; i < dataTransfer.types.length; i++) {
+    let type = dataTransfer.types[i]
+    if (type && type.startsWith('application/x-brave-')) {
+      return true
+    }
+  }
+  return false
+}
+
+function blockDndData (e) {
+  if (hasBraveDragData(e.dataTransfer)) {
+    // Block drag data from the Brave UI
+    try {
+      e.dataTransfer.dropEffect = 'none'
+    } catch (e) {}
+    e.preventDefault()
+    e.stopPropagation()
+    return false
+  }
+  return true
+}
+
+window.addEventListener('dragover', blockDndData, true)
+window.addEventListener('dragenter', blockDndData, true)
+window.addEventListener('dragleave', blockDndData, true)
+window.addEventListener('drop', blockDndData, true)

app/extensions/brave/content/scripts/inputHandler.js

@@ -151,34 +151,3 @@ document.addEventListener('keydown', (e /*: Event*/) => {
       break
   }
 })
-
-function hasBraveDragData (dataTransfer) {
-  if (!dataTransfer || !dataTransfer.types) {
-    return false
-  }
-  for (let i = 0; i < dataTransfer.types.length; i++) {
-    let type = dataTransfer.types[i]
-    if (type && type.startsWith('application/x-brave-')) {
-      return true
-    }
-  }
-  return false
-}
-
-function blockDndData (e) {
-  if (hasBraveDragData(e.dataTransfer)) {
-    // Block drag data from the Brave UI
-    try {
-      e.dataTransfer.dropEffect = 'none'
-    } catch (e) {}
-    e.preventDefault()
-    e.stopPropagation()
-    return false
-  }
-  return true
-}
-
-window.addEventListener('dragover', blockDndData, true)
-window.addEventListener('dragenter', blockDndData, true)
-window.addEventListener('dragleave', blockDndData, true)
-window.addEventListener('drop', blockDndData, true)