Fix .equals() logic in Profile class

Summary: The existing `.equals()` method was throwing null pointer exceptions if certain fields of the `Profile` were null (which they are allowed to be, since we have explicitly specified that they are `nullable`). Fix this logic and add a sanity check to confirm that `.equals()` is indeed commutative.

Reviewed By: YOUDAN

Differential Revision: D24284819

fbshipit-source-id: 4efc3d3ac3228f3251a2e3d2c8e44a7f4fb93260

facebook-core/src/main/java/com/facebook/Profile.java

@@ -221,17 +221,12 @@ public boolean equals(Object other) {
 
     Profile o = (Profile) other;
 
-    return id.equals(o.id) && firstName == null
-        ? o.firstName == null
-        : firstName.equals(o.firstName) && middleName == null
-            ? o.middleName == null
-            : middleName.equals(o.middleName) && lastName == null
-                ? o.lastName == null
-                : lastName.equals(o.lastName) && name == null
-                    ? o.name == null
-                    : name.equals(o.name) && linkUri == null
-                        ? o.linkUri == null
-                        : linkUri.equals(o.linkUri);
+    return (id == null ? o.id == null : id.equals(o.id))
+        && (firstName == null ? o.firstName == null : firstName.equals(o.firstName))
+        && (middleName == null ? o.middleName == null : middleName.equals(o.middleName))
+        && (lastName == null ? o.lastName == null : lastName.equals(o.lastName))
+        && (name == null ? o.name == null : name.equals(o.name))
+        && (linkUri == null ? o.linkUri == null : linkUri.equals(o.linkUri));
   }
 
   @Override

facebook/src/test/java/com/facebook/ProfileTest.java

@@ -90,6 +90,7 @@ public void testEquals() {
 
     Profile profile3 = createMostlyNullsProfile();
     assertNotEquals(profile1, profile3);
+    assertNotEquals(profile3, profile1);
   }
 
   @Test