Cleaned up some slot logic

Doesn't look like we actually need current_slot, since we can always
just call function get_current_slot

Test: tested flashall on raven
Change-Id: Icba64bc9fdd08f36d44965e32558a73d0beab0e1
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 42269fe..b977e31 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -1560,10 +1560,10 @@
     }
 }
 
-std::string GetPartitionName(const ImageEntry& entry, std::string& current_slot) {
+std::string GetPartitionName(const ImageEntry& entry) {
     auto slot = entry.second;
     if (slot.empty()) {
-        slot = current_slot;
+        slot = get_current_slot();
     }
     if (slot.empty()) {
         return entry.first->part_name;
@@ -1582,7 +1582,7 @@
 
   private:
     void CheckRequirements();
-    void DetermineSlot();
+    void DetermineSecondarySlot();
     void CollectImages();
     void FlashImages(const std::vector<std::pair<const Image*, std::string>>& images);
     void FlashImage(const Image& image, const std::string& slot, fastboot_buffer* buf);
@@ -1600,15 +1600,13 @@
 
     // Change the slot first, so we boot into the correct recovery image when
     // using fastbootd.
-    if (fp_->slot == "all") {
+    if (fp_->slot_override == "all") {
         set_active("a");
     } else {
-        set_active(fp_->slot);
+        set_active(fp_->slot_override);
     }
 
-    DetermineSlot();
-    CollectImages();
-
+    DetermineSecondarySlot();
     CancelSnapshotIfNeeded();
 
     // First flash boot partitions. We allow this to happen either in userspace
@@ -1653,18 +1651,12 @@
     ::CheckRequirements({contents.data(), contents.size()}, fp_->force_flash);
 }
 
-void FlashAllTool::DetermineSlot() {
-    if (fp_->slot.empty()) {
-        fp_->current_slot = get_current_slot();
-    } else {
-        fp_->current_slot = fp_->slot;
-    }
-
+void FlashAllTool::DetermineSecondarySlot() {
     if (fp_->skip_secondary) {
         return;
     }
-    if (fp_->slot != "" && fp_->slot != "all") {
-        fp_->secondary_slot = get_other_slot(fp_->slot);
+    if (fp_->slot_override != "" && fp_->slot_override != "all") {
+        fp_->secondary_slot = get_other_slot(fp_->slot_override);
     } else {
         fp_->secondary_slot = get_other_slot();
     }
@@ -1678,7 +1670,7 @@
 
 void FlashAllTool::CollectImages() {
     for (size_t i = 0; i < images.size(); ++i) {
-        std::string slot = fp_->slot;
+        std::string slot = fp_->slot_override;
         if (images[i].IsSecondary()) {
             if (fp_->skip_secondary) {
                 continue;
diff --git a/fastboot/fastboot.h b/fastboot/fastboot.h
index c954487..029b583 100644
--- a/fastboot/fastboot.h
+++ b/fastboot/fastboot.h
@@ -80,8 +80,7 @@
     bool skip_secondary = false;
     bool force_flash = false;
 
-    std::string slot;
-    std::string current_slot;
+    std::string slot_override;
     std::string secondary_slot;
     fastboot::FastBootDriver* fb;
 };
@@ -103,7 +102,7 @@
 
 Result<NetworkSerial, FastbootError> ParseNetworkSerial(const std::string& serial);
 bool supports_AB();
-std::string GetPartitionName(const ImageEntry& entry, std::string& current_slot_);
+std::string GetPartitionName(const ImageEntry& entry);
 void flash_partition_files(const std::string& partition, const std::vector<SparsePtr>& files);
 int64_t get_sparse_limit(int64_t size);
 std::vector<SparsePtr> resparse_file(sparse_file* s, int64_t max_size);
diff --git a/fastboot/task.cpp b/fastboot/task.cpp
index 9d4cb75..3d2c975 100644
--- a/fastboot/task.cpp
+++ b/fastboot/task.cpp
@@ -95,7 +95,7 @@
         LOG(VERBOSE) << "Cannot optimize flashing super on non-AB device";
         return nullptr;
     }
-    if (fp->slot == "all") {
+    if (fp->slot_override == "all") {
         LOG(VERBOSE) << "Cannot optimize flashing super for all slots";
         return nullptr;
     }
@@ -132,7 +132,7 @@
     }
 
     for (const auto& entry : os_images) {
-        auto partition = GetPartitionName(entry, fp->current_slot);
+        auto partition = GetPartitionName(entry);
         auto image = entry.first;
 
         if (!helper->AddPartition(partition, image->img_name, image->optional_if_no_image)) {
@@ -145,7 +145,7 @@
 
     // Remove images that we already flashed, just in case we have non-dynamic OS images.
     auto remove_if_callback = [&](const ImageEntry& entry) -> bool {
-        return helper->WillFlash(GetPartitionName(entry, fp->current_slot));
+        return helper->WillFlash(GetPartitionName(entry));
     };
     os_images.erase(std::remove_if(os_images.begin(), os_images.end(), remove_if_callback),
                     os_images.end());