Copybara ❤️: Add ability to check if change ID is enabled in current process.

CL: cl/586267157
PiperOrigin-RevId: 586267157
Change-Id: I37a12c38a3fb192b880d5241f65b5be5674f9496

src/com/android/onboarding/versions/OnboardingChanges.kt

diff --git a/src/com/android/onboarding/versions/OnboardingChanges.kt b/src/com/android/onboarding/versions/OnboardingChanges.kt
new file mode 100644
index 0000000..2c4d3eb
--- /dev/null
+++ b/src/com/android/onboarding/versions/OnboardingChanges.kt
@@ -0,0 +1,65 @@
+package com.android.onboarding.versions
+
+import android.content.Context
+import android.provider.Settings
+
+/** Entry point to checking if processes support particular change ids. */
+interface OnboardingChanges {
+
+  /**
+   * True if the current executing process supports the given change ID.
+   *
+   * The changeId must reference a long constant annotated with
+   * [com.android.onboarding.versions.annotations.ChangeId]
+   */
+  fun currentProcessSupportsChange(changeId: Long): Boolean
+}
+
+/**
+ * Default implementation of [OnboardingChanges].
+ *
+ * For local testing, use `adb shell settings put global package.name.changeid 1` to enable and `adb
+ * shell settings put global package.name.changeid 0` to disable. For example to enable change ID
+ * 1234 on package `com.android.setup` we would use `adb shell settings put global
+ * com.android.setup.1234 1`. You can also use `adb shell settings delete global
+ * package.name.changeid` to use the default configured value.
+ */
+class DefaultOnboardingChanges(val context: Context) : OnboardingChanges {
+  override fun currentProcessSupportsChange(changeId: Long): Boolean {
+    // First we check for global setting override (for local testing)
+    val changeOverride = getChangeOverride(context.packageName, changeId)
+    if (changeOverride != null) {
+      return changeOverride
+    }
+
+    return false
+  }
+
+  private fun getChangeOverride(packageName: String, changeId: Long): Boolean? {
+    val settingKey = "$packageName.$changeId"
+
+    return try {
+      Settings.Global.getInt(context.contentResolver, settingKey) == 1
+    } catch (e: Settings.SettingNotFoundException) {
+      null
+    }
+  }
+}
+
+/** Fake implementation of [OnboardingChanges]. */
+class FakeOnboardingChanges : OnboardingChanges {
+
+  val supportedChanges = mutableSetOf<Long>()
+
+  override fun currentProcessSupportsChange(changeId: Long): Boolean {
+    return supportedChanges.contains(changeId)
+  }
+
+  fun enableChange(changeId: Long) {
+    supportedChanges.add(changeId)
+  }
+
+  fun disableChange(changeId: Long) {
+    supportedChanges.remove(changeId)
+  }
+}