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

jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantChanged/const.kt

@@ -1,7 +1,7 @@
 package test
 
 class Klass {
-    class object {
+    default object {
         // Old and new constant values are different, but their hashes are the same
         val CONST = "BF"
     }

jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantChanged/const.kt.new

@@ -1,7 +1,7 @@
 package test
 
 class Klass {
-    class object {
+    default object {
         // Old and new constant values are different, but their hashes are the same
         val CONST = "Ae"
     }

jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantUnchanged/const.kt

@@ -1,7 +1,7 @@
 package test
 
 class Klass {
-    class object {
+    default object {
         val CONST = "bar"
     }
 }

jps-plugin/testData/incremental/withJava/kotlinUsedInJava/constantUnchanged/const.kt.new

@@ -1,7 +1,7 @@
 package test
 
 class Klass {
-    class object {
+    default object {
         val CONST = "bar"
     }
 }