Return a result in Page.getFrameTree

Signed-off-by: Francis Bouvier <francis@lightpanda.io>

src/cdp/page.zig

@@ -41,14 +41,37 @@ fn enable(
     return result(alloc, id, null, null, sessionID);
 }
 
+const FrameTreeID = "90D14BBD8AED408A0467AC93100BCDBE";
+const LoaderID = "CFC8BED824DD2FD56CF1EF33C965C79C";
+const URLBase = "chrome://newtab/";
+
 fn getFrameTree(
     alloc: std.mem.Allocator,
     id: u64,
-    _: *std.json.Scanner,
+    scanner: *std.json.Scanner,
     _: *Ctx,
 ) ![]const u8 {
-    // TODO: dummy
+    const sessionID = try cdp.getSessionID(scanner);
-    return result(alloc, id, null, null, null);
+    const FrameTree = struct {
+        frameTree: struct {
+            frame: struct {
+                id: []const u8 = FrameTreeID,
+                loaderId: []const u8 = LoaderID,
+                url: []const u8 = URLBase,
+                domainAndRegistry: []const u8 = "",
+                securityOrigin: []const u8 = URLBase,
+                mimeType: []const u8 = "mimeType",
+                adFrameStatus: struct {
+                    adFrameType: []const u8 = "none",
+                } = .{},
+                secureContextType: []const u8 = "Secure",
+                crossOriginIsolatedContextType: []const u8 = "NotIsolated",
+                gatedAPIFeatures: [][]const u8 = &[0][]const u8{},
+            } = .{},
+        } = .{},
+        childFrames: ?[]@This() = null,
+    };
+    return result(alloc, id, FrameTree, FrameTree{}, sessionID);
 }
 
 fn setLifecycleEventsEnabled(