Fix NPE in the parsing of property file.

this could happen if the log object is null and the parsing fails.

Change-Id: I6dbcafab26c5405efba20b30f511104fcee5bf78

tools/sdkmanager/libs/sdklib/src/com/android/sdklib/SdkManager.java

@@ -605,8 +605,10 @@ public final class SdkManager {
                     if (m.matches()) {
                         map.put(m.group(1), m.group(2));
                     } else {
+                        if (log != null) {
                             log.warning("Error parsing '%1$s': \"%2$s\" is not a valid syntax",
                                     buildProp.getAbsolutePath(), line);
+                        }
                         return null;
                     }
                 }