Handle the OpenDocument event in GAPIC.

This event is sent on OSX if the user requests GAPID to open a gfxtrace
file, for example via double-clicking on a gfxtrace file in the Finder.
This event is sent if the application is already running, or if it just
has been started in response to opening a file.

gapic/src/main/com/google/gapid/MainWindow.java

@@ -184,7 +184,8 @@ public void onCopyEnabled(boolean enabled) {
     if (OS.isMac) {
       MacApplication.init(shell.getDisplay(),
           () -> showAbout(shell, widgets().theme),
-          () -> showSettingsDialog(shell, models().settings));
+          () -> showSettingsDialog(shell, models().settings),
+          file -> models().capture.loadCapture(new File(file)));
     }
   }
 

gapic/src/main/com/google/gapid/util/MacApplication.java

@@ -20,6 +20,8 @@
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.MenuItem;
 
+import java.util.function.Consumer;
+
 /**
  * Special handling for OSX application menus.
  */
@@ -30,7 +32,8 @@ private MacApplication() {
   /**
    * Initializes the OSX application menus.
    */
-  public static void init(Display display, Runnable onAbout, Runnable onSettings) {
+  public static void init(
+      Display display, Runnable onAbout, Runnable onSettings, Consumer<String> onOpen) {
     Menu menu = display.getSystemMenu();
     if (menu == null) {
       return;
@@ -46,5 +49,7 @@ public static void init(Display display, Runnable onAbout, Runnable onSettings)
           break;
       }
     }
+
+    display.addListener(SWT.OpenDocument, e -> onOpen.accept(e.text));
   }
 }