Revert "do not map partitions on A/B devices"

This reverts commit 50d4d9d80dfd804bcd8c49893e0cd15cbb55a5e3.

Reason for revert: Staging revert so we can test if this is the root cause of b/394735624

Change-Id: If5970a9c0ab5e132a584092cb404ed32671e5d50
diff --git a/payload_consumer/postinstall_runner_action.cc b/payload_consumer/postinstall_runner_action.cc
index 84237b1..1717dd7 100644
--- a/payload_consumer/postinstall_runner_action.cc
+++ b/payload_consumer/postinstall_runner_action.cc
@@ -111,17 +111,12 @@
   // If we are switching slots, then we are required to MapAllPartitions,
   // as FinishUpdate() requires all partitions to be mapped.
   // And switching slots requires FinishUpdate() to be called first
-  if (dynamic_control->GetVirtualAbFeatureFlag().IsEnabled()) {
-    // If we are switching slots, then we are required to MapAllPartitions,
-    // as FinishUpdate() requires all partitions to be mapped.
-    // And switching slots requires FinishUpdate() to be called first
-    if (!install_plan_.partitions.empty() ||
-        install_plan_.switch_slot_on_reboot) {
-      if (!dynamic_control->MapAllPartitions()) {
-        LOG(ERROR) << "Failed to map all partitions, this would cause "
-                      "FinishUpdate to fail. Abort early.";
-        return CompletePostinstall(ErrorCode::kPostInstallMountError);
-      }
+  if (!install_plan_.partitions.empty() ||
+      install_plan_.switch_slot_on_reboot) {
+    if (!dynamic_control->MapAllPartitions()) {
+      LOG(ERROR) << "Failed to map all partitions, this would cause "
+                    "FinishUpdate to fail. Abort early.";
+      return CompletePostinstall(ErrorCode::kPostInstallMountError);
     }
   }