Add the missing O target

1. Add the missing O target
   (I thought the default one is built, but it is not)
2. Build.VERSION_CODES.O can be both 26 and 10000, handle both cases

Change-Id: Ida39ed17c75d048c921a9953a4d16b5fbe84097b
Fix: 38220744

Author: tony-mak

app/build.gradle

@@ -19,7 +19,7 @@ android {
     defaultConfig {
         applicationId "com.afwsamples.testdpc"
         minSdkVersion 21
-        targetSdkVersion 25
+        targetSdkVersion 26
         versionCode versionMajor * 1000 + versionMinor * 100 + versionBuild
         versionName "${versionMajor}.${versionMinor}.${versionBuild}"
         jackOptions {
@@ -38,6 +38,10 @@ android {
         target25 {
             targetSdkVersion 25
         }
+
+        targetO {
+            targetSdkVersion 'O'
+        }
     }
 
     lintOptions {

app/src/main/java/com/afwsamples/testdpc/common/preference/DpcPreferenceHelper.java

@@ -220,7 +220,8 @@ public void disableIfConstraintsNotMet() {
      */
     private CharSequence findConstraintViolation() {
         if (getDeviceSdkInt() < mMinSdkVersion) {
-            if (mMinSdkVersion == Build.VERSION_CODES.O) {
+            // FIXME: Remove this special checking once O is out.
+            if (mMinSdkVersion >= 26) {
                 return mContext.getString(R.string.requires_preview_release);
             }
             return mContext.getString(R.string.requires_android_api_level, mMinSdkVersion);

app/src/main/res/values/attrs.xml

@@ -25,8 +25,8 @@
             <enum name="L" value="21" />
             <enum name="M" value="23" />
             <enum name="N" value="24" />
+            <enum name="O" value="26" />
             <!-- Build.VERSION_CODES.CUR_DEVELOPMENT, fill in the sdk int once it is finalized -->
-            <enum name="O" value="10000" />
         </attr>
 
         <!-- Constrain a preference to DO or PO admins. -->
@@ -55,4 +55,4 @@
             <flag name="any" value="0x7" /> <!-- default -->
         </attr>
     </declare-styleable>
-</resources>
+</resources>