Ready module.jsons for multi-keypress shortcuts

Currently, ShortcutRegistry allows multiple shortcuts to be stored
within the same binding in a module.json, e.g. `"shortcut": "F8
Ctrl+\\"` creates two shortcuts, one on F8 and another on Ctrl+\. When
multi-keypress shortcuts/chords are added in the future, they'll use the
same format such that the above example would be interpreted as a single
shortcut bound to the F8 Ctrl+\ sequence. In order to allow that, it's
necessary to split up all of the existing shortcuts that are stored in
space-delimited strings so that they'll continue to function as
expected. This CL also updates the module.schema.json to disallow spaces
in shortcuts, a restriction that will be removed once multi-keypress
shortcuts are implemented.

Custom keyboard shortcuts design doc: https://docs.google.com/document/d/1oOPSWPxCHvMoBZ0Fw9jwFZt6gP4lrsrsl8DEAp-Hy7o/edit#heading=h.2xpjzz3fl1ju

Bug: 174309
Change-Id: I853f9918ad2892b2f4c4f3aec53013d7a6455f67
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2123807
Reviewed-by: Robert Paveza <[email protected]>
Reviewed-by: Vidal Diazleal <[email protected]>
Commit-Queue: Jack Lynch <[email protected]>
diff --git a/front_end/ui/ShortcutRegistry.js b/front_end/ui/ShortcutRegistry.js
index ea1b46f..7a25cc4 100644
--- a/front_end/ui/ShortcutRegistry.js
+++ b/front_end/ui/ShortcutRegistry.js
@@ -237,14 +237,11 @@
         if (!platformMatches(bindings[i].platform)) {
           continue;
         }
-        const shortcuts = bindings[i].shortcut.split(/\s+/);
-        shortcuts.forEach(shortcut => {
-          const shortcutDescriptor = KeyboardShortcut.makeDescriptorFromBindingShortcut(shortcut);
-          if (shortcutDescriptor) {
-            this._registerShortcut(new KeyboardShortcut(
-                shortcutDescriptor, /** @type {string} */ (descriptor.actionId), Type.DefaultShortcut));
-          }
-        });
+        const shortcutDescriptor = KeyboardShortcut.makeDescriptorFromBindingShortcut(bindings[i].shortcut);
+        if (shortcutDescriptor) {
+          this._registerShortcut(new KeyboardShortcut(
+              shortcutDescriptor, /** @type {string} */ (descriptor.actionId), Type.DefaultShortcut));
+        }
       }
     }