Remove some ref churn in CFX_DefaultRenderDevice::AttachImpl().

Use std::move() on more bitmaps.

Change-Id: I8980cb9a42efcac701ca7f3a1e0669d8db995f22
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/102771
Reviewed-by: Nigi <nigi@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/core/fxge/cfx_defaultrenderdevice.cpp b/core/fxge/cfx_defaultrenderdevice.cpp
index 912db62..fc61b58 100644
--- a/core/fxge/cfx_defaultrenderdevice.cpp
+++ b/core/fxge/cfx_defaultrenderdevice.cpp
@@ -69,11 +69,12 @@
     bool bGroupKnockout) {
 #ifdef _SKIA_SUPPORT_
   if (SkiaIsDefaultRenderer()) {
-    return AttachSkiaImpl(pBitmap, bRgbByteOrder, pBackdropBitmap,
-                          bGroupKnockout);
+    return AttachSkiaImpl(std::move(pBitmap), bRgbByteOrder,
+                          std::move(pBackdropBitmap), bGroupKnockout);
   }
 #endif
-  return AttachAggImpl(pBitmap, bRgbByteOrder, pBackdropBitmap, bGroupKnockout);
+  return AttachAggImpl(std::move(pBitmap), bRgbByteOrder,
+                       std::move(pBackdropBitmap), bGroupKnockout);
 }
 
 bool CFX_DefaultRenderDevice::Create(int width,