This plugin gets built named "clang-scanbuild" as its shortname defined in the build.gradle file.

shortName = 'clang-scanbuild'

The file ClangScanBuildUtils.java has the following definition which is uses to location the plugin icons:

public static final String SHORTNAME = "clang-scanbuild-plugin";
public static String getIconsPath(){
	return "/plugin/" + SHORTNAME + "/icons/";
}

This causes the icon path to be incorrect and the icon to 404 in the sidebar for the "Clang scan-build trend" link.