Replace 'class object' with 'default object' in renderers and test data

Includes changes to decompiled text
Old syntax is used in builtins and project code for now

compiler/testData/compileJavaAgainstKotlin/staticFields/AnnotationClass.kt

@@ -10,7 +10,7 @@ annotation class AFloat(val value: Float)
 
 class Test {
 
-    class object {
+    default object {
         val vstring: String = "Test"
         val vchar: Char = 'c'
         val vint: Int = 10

compiler/testData/compileJavaAgainstKotlin/staticFields/AnnotationTrait.kt

@@ -10,7 +10,7 @@ annotation class AFloat(val value: Float)
 
 trait Test {
 
-    class object {
+    default object {
         val vstring: String = "Test"
         val vchar: Char = 'c'
         val vint: Int = 10

compiler/testData/compileJavaAgainstKotlin/staticFields/kt3698.kt

@@ -1,7 +1,7 @@
 package test
 
 class KotlinClass {
-    class object {
+    default object {
         val FOO: Int = 10
     }
 }

compiler/testData/compileJavaAgainstKotlin/staticFields/staticClassProperty.kt

@@ -2,7 +2,7 @@ package test
 
 class Test {
 
-  class object {
+  default object {
     public val valProp: Int = 10
 
     public var varProp: Int = 10

compiler/testData/compileJavaAgainstKotlin/staticFields/staticTraitProperty.kt

@@ -2,7 +2,7 @@ package test
 
 trait Test {
 
-  class object {
+  default object {
     public val valProp: Int = 10
   }