Auto-build/update codegen

Test: 1. Manually enter version/presence of build artifact,
and ensure `codegen FILENAME` still works
2. run codegen again without altering version, ensure no build triggered
Change-Id: I6f1dba0a476077c708bbea8ef558445107e5ad97
diff --git a/tools/codegen/Android.bp b/tools/codegen/Android.bp
index 805b296..677bee2 100644
--- a/tools/codegen/Android.bp
+++ b/tools/codegen/Android.bp
@@ -1,5 +1,5 @@
 java_binary_host {
-    name: "codegen",
+    name: "codegen_cli",
     manifest: "manifest.txt",
     srcs: [
         "src/**/*.kt",
diff --git a/tools/codegen/src/com/android/codegen/SharedConstants.kt b/tools/codegen/src/com/android/codegen/SharedConstants.kt
index 41641f6..175eea6 100644
--- a/tools/codegen/src/com/android/codegen/SharedConstants.kt
+++ b/tools/codegen/src/com/android/codegen/SharedConstants.kt
@@ -1,4 +1,4 @@
 package com.android.codegen
 
 const val CODEGEN_NAME = "codegen"
-const val CODEGEN_VERSION = "0.0.1"
\ No newline at end of file
+const val CODEGEN_VERSION = "1.0.0"
\ No newline at end of file
diff --git a/tools/processors/staledataclass/src/android/processor/staledataclass/StaleDataclassProcessor.kt b/tools/processors/staledataclass/src/android/processor/staledataclass/StaleDataclassProcessor.kt
index 9e51180..e5ec17a 100644
--- a/tools/processors/staledataclass/src/android/processor/staledataclass/StaleDataclassProcessor.kt
+++ b/tools/processors/staledataclass/src/android/processor/staledataclass/StaleDataclassProcessor.kt
@@ -125,6 +125,7 @@
 
         val lastGenerated = annotationParams["time"] as Long
         val codegenVersion = annotationParams["codegenVersion"] as String
+        val codegenMajorVersion = codegenVersion.substringBefore(".")
         val sourceRelative = File(annotationParams["sourceFile"] as String)
 
         val lastGenInputSignatures = (annotationParams["inputSignatures"] as String).lines().toSet()
@@ -151,7 +152,7 @@
             stale += Stale(clazz, source, lastGenerated)
         }
 
-        if (codegenVersion != CODEGEN_VERSION) {
+        if (codegenMajorVersion != CODEGEN_VERSION.substringBefore(".")) {
             stale += Stale(clazz, source, lastGenerated)
         }
     }