Make aliased variables' scope to function level

It seems minidumps fail to include "reason". My guess
is it's due to its if-else-clause local scope.

Declare these variables at function level, hoping they
will be included in minidumps.

BUG=1060785,1077725
TEST=bots
R=rafael.cintron@microsoft.com

Change-Id: I0a81aee1134c4c69c1d444b6b445b07dc99d9ccc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2515223
Commit-Queue: Zhenyao Mo <zmo@chromium.org>
Reviewed-by: Rafael Cintron <rafael.cintron@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#823427}

ui/gl/direct_composition_child_surface_win.cc

@@ -135,11 +135,12 @@ bool DirectCompositionChildSurfaceWin::ReleaseDrawTexture(bool will_discard) {
   if (dcomp_surface_.Get() == g_current_surface)
     g_current_surface = nullptr;
 
+  HRESULT hr, device_removed_reason;
   if (draw_texture_) {
     draw_texture_.Reset();
     if (dcomp_surface_) {
       TRACE_EVENT0("gpu", "DirectCompositionChildSurfaceWin::EndDraw");
-      HRESULT hr = dcomp_surface_->EndDraw();
+      hr = dcomp_surface_->EndDraw();
       if (FAILED(hr)) {
         DLOG(ERROR) << "EndDraw failed with error " << std::hex << hr;
         return false;
@@ -155,7 +156,6 @@ bool DirectCompositionChildSurfaceWin::ReleaseDrawTexture(bool will_discard) {
       TRACE_EVENT2("gpu", "DirectCompositionChildSurfaceWin::PresentSwapChain",
                    "interval", interval, "dirty_rect",
                    force_full_damage_ ? "full_damage" : swap_rect_.ToString());
-      HRESULT hr;
       if (force_full_damage_) {
         hr = swap_chain_->Present(interval, flags);
       } else {
@@ -204,9 +204,9 @@ bool DirectCompositionChildSurfaceWin::ReleaseDrawTexture(bool will_discard) {
         if (SUCCEEDED(hr)) {
           event.Wait();
         } else {
+          device_removed_reason = d3d11_device_->GetDeviceRemovedReason();
           base::debug::Alias(&hr);
-          HRESULT reason = d3d11_device_->GetDeviceRemovedReason();
-          base::debug::Alias(&reason);
+          base::debug::Alias(&device_removed_reason);
           base::debug::DumpWithoutCrashing();
         }
       }

ui/gl/swap_chain_presenter.cc

@@ -842,10 +842,11 @@ bool SwapChainPresenter::PresentToSwapChain(
     return false;
   }
 
+  HRESULT hr, device_removed_reason;
   if (first_present_) {
     first_present_ = false;
     UINT flags = DXGI_PRESENT_USE_DURATION;
-    HRESULT hr = swap_chain_->Present(0, flags);
+    hr = swap_chain_->Present(0, flags);
     // Ignore DXGI_STATUS_OCCLUDED since that's not an error but only indicates
     // that the window is occluded and we can stop rendering.
     if (FAILED(hr) && hr != DXGI_STATUS_OCCLUDED) {
@@ -882,9 +883,9 @@ bool SwapChainPresenter::PresentToSwapChain(
     if (SUCCEEDED(hr)) {
       event.Wait();
     } else {
+      device_removed_reason = d3d11_device_->GetDeviceRemovedReason();
       base::debug::Alias(&hr);
-      HRESULT reason = d3d11_device_->GetDeviceRemovedReason();
-      base::debug::Alias(&reason);
+      base::debug::Alias(&device_removed_reason);
       base::debug::DumpWithoutCrashing();
     }
   }
@@ -895,7 +896,7 @@ bool SwapChainPresenter::PresentToSwapChain(
   UINT interval = use_swap_chain_tearing ? 0 : 1;
   // Ignore DXGI_STATUS_OCCLUDED since that's not an error but only indicates
   // that the window is occluded and we can stop rendering.
-  HRESULT hr = swap_chain_->Present(interval, flags);
+  hr = swap_chain_->Present(interval, flags);
   if (FAILED(hr) && hr != DXGI_STATUS_OCCLUDED) {
     DLOG(ERROR) << "Present failed with error 0x" << std::hex << hr;
     return false;