minui: GRSurface manages data with std::unique_ptr.

Test: Run recovery_unit_test on marlin.
Test: `Run graphics test` on taimen.
Change-Id: I34bd862049900b0030f2840a92a7fa3e02fa2c10
diff --git a/minui/resources.cpp b/minui/resources.cpp
index 9027bc6..c7af190 100644
--- a/minui/resources.cpp
+++ b/minui/resources.cpp
@@ -46,24 +46,19 @@
   auto result = std::unique_ptr<GRSurface>(new GRSurface(width, height, row_bytes, pixel_bytes));
   result->data_size_ =
       (data_size + kSurfaceDataAlignment - 1) / kSurfaceDataAlignment * kSurfaceDataAlignment;
-  result->data_ = static_cast<uint8_t*>(aligned_alloc(kSurfaceDataAlignment, result->data_size_));
-  if (result->data_ == nullptr) return nullptr;
+  result->data_.reset(
+      static_cast<uint8_t*>(aligned_alloc(kSurfaceDataAlignment, result->data_size_)));
+  if (!result->data_) return nullptr;
   return result;
 }
 
 std::unique_ptr<GRSurface> GRSurface::Clone() const {
   auto result = GRSurface::Create(width, height, row_bytes, pixel_bytes, data_size_);
-  memcpy(result->data_, data_, data_size_);
+  if (!result) return nullptr;
+  memcpy(result->data(), data(), data_size_);
   return result;
 }
 
-GRSurface::~GRSurface() {
-  if (data_ != nullptr) {
-    free(data_);
-    data_ = nullptr;
-  }
-}
-
 PngHandler::PngHandler(const std::string& name) {
   std::string res_path = g_resource_dir + "/" + name + ".png";
   png_fp_.reset(fopen(res_path.c_str(), "rbe"));