default -> companion: replace all mentions of default and default object

idea/testData/resolve/referenceInJava/ClassObjectField.java

@@ -1,7 +1,7 @@
 public class ClassObjectField {
     public static void foo() {
-        k.ClassWithClassObject.De<caret>fault.f();
+        k.ClassWithClassObject.Co<caret>mpanion.f();
     }
 }
 
-// REF: default object of (k).ClassWithClassObject
+// REF: companion object of (k).ClassWithClassObject

idea/testData/resolve/referenceInJava/ClassObjectStaticField.java

@@ -6,4 +6,4 @@ public class ClassObjectField {
     }
 }
 
-// REF: (k.StaticFieldInClassObjectInTrait.Default).XX
+// REF: (k.StaticFieldInClassObjectInTrait.Companion).XX

idea/testData/resolve/referenceInJava/DeprecatedClassObjectField.java

@@ -4,4 +4,4 @@ public class ClassObjectField {
     }
 }
 
-// REF: default object of (k).ClassWithClassObject
+// REF: companion object of (k).ClassWithClassObject

idea/testData/resolve/referenceInJava/dependencies.kt

@@ -16,7 +16,7 @@ public fun topLevelFun() {
 }
 
 public class ClassWithClassObject {
-    default object {
+    companion object {
         fun f() = 1
     }
 }
@@ -26,7 +26,7 @@ public object KotlinObject {
 }
 
 public trait StaticFieldInClassObjectInTrait {
-    default object {
+    companion object {
         public val XX: String = "xx"
     }
 }