added @Nullable to some optional fields of ApplicationInfo

platform/core-api/src/com/intellij/openapi/application/ApplicationInfo.java

@@ -17,6 +17,7 @@ package com.intellij.openapi.application;
 
 import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.util.BuildNumber;
+import org.jetbrains.annotations.Nullable;
 
 import java.awt.*;
 import java.util.Calendar;
@@ -46,11 +47,12 @@ public abstract class ApplicationInfo {
    */
   public abstract String getShortCompanyName();
   public abstract String getCompanyURL();
+  @Nullable
   public abstract String getThirdPartySoftwareURL();
   public abstract String getJetbrainsTvUrl();
   public abstract String getEvalLicenseUrl();
   public abstract String getKeyConversionUrl();
-
+  @Nullable
   public abstract Rectangle getAboutLogoRect();
   public abstract boolean hasHelp();
   public abstract boolean hasContextHelp();

platform/core-impl/src/com/intellij/openapi/application/impl/ApplicationInfoImpl.java

@@ -526,6 +526,7 @@ public class ApplicationInfoImpl extends ApplicationInfoEx {
     return myAboutForeground;
   }
 
+  @Nullable
   public Color getAboutLinkColor() {
     return myAboutLinkColor;
   }