MacKeyboard: Don't generate keypress for non-printable char

content/browser/renderer_host/render_widget_host_view_mac.mm

Index: content/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index 8f6dab7704df8125980e2c368414d68fbcfe3020..c4cef662fb03952bc74ae4d365ed8290650604f1 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -2297,6 +2297,7 @@ void RenderWidgetHostViewMac::OnDisplayMetricsChanged(
       widgetHost->ForwardKeyboardEvent(event);
     } else if ((!textInserted || delayEventUntilAfterImeCompostion) &&
                [[theEvent characters] length] > 0 &&
+               base::mac::StringIsPrintable([theEvent characters]) &&
                (([theEvent modifierFlags] & kCtrlCmdKeyMask) ||
                 (hasEditCommands_ && editCommands_.empty()))) {
       // We don't get insertText: calls if ctrl or cmd is down, or the key event