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

compiler/testData/writeFlags/function/classObjectPrivate/privateFun.kt

@@ -2,7 +2,7 @@ class Foo {
 
   {Foo.test()}
 
-  default object {
+  companion object {
     private fun test() {
 
     }
@@ -10,5 +10,5 @@ class Foo {
 }
 
 // TESTED_OBJECT_KIND: function
-// TESTED_OBJECTS: Foo$Default, test
+// TESTED_OBJECTS: Foo$Companion, test
 // FLAGS: ACC_PRIVATE, ACC_FINAL

compiler/testData/writeFlags/function/classObjectPrivate/privateVal.kt

@@ -2,11 +2,11 @@ class Foo {
 
   {Foo.test}
 
-  default object {
+  companion object {
     private val test = "String"
   }
 }
 
 // TESTED_OBJECT_KIND: function
-// TESTED_OBJECTS: Foo$Default, getTest
+// TESTED_OBJECTS: Foo$Companion, getTest
 // FLAGS: ACC_PRIVATE, ACC_FINAL

compiler/testData/writeFlags/function/classObjectPrivate/privateVar.kt

@@ -2,11 +2,11 @@ class Foo {
 
   {Foo.test}
 
-  default object {
+  companion object {
     private var test = "String"
   }
 }
 
 // TESTED_OBJECT_KIND: function
-// TESTED_OBJECTS: Foo$Default, setTest
+// TESTED_OBJECTS: Foo$Companion, setTest
 // FLAGS: ACC_PRIVATE, ACC_FINAL