Revert "Revert "move device headers to core""

This reverts commit d4bdee5f2c.

BUG=skia:

Change-Id: If5c316f8585881e43321412a2a38f97fd4aa5f02
Reviewed-on: https://skia-review.googlesource.com/7315
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>

gn/core.gni

@@ -30,6 +30,7 @@ skia_core_sources = [
   "$_src/core/SkBitmapCache.cpp",
   "$_src/core/SkBitmapController.cpp",
   "$_src/core/SkBitmapDevice.cpp",
+  "$_src/core/SkBitmapDevice.h",
   "$_src/core/SkBitmapFilter.h",
   "$_src/core/SkBitmapProcShader.cpp",
   "$_src/core/SkBitmapProcShader.h",
@@ -102,6 +103,7 @@ skia_core_sources = [
   "$_src/core/SkDeque.cpp",
   "$_src/core/SkDescriptor.h",
   "$_src/core/SkDevice.cpp",
+  "$_src/core/SkDevice.h",
   "$_src/core/SkDeviceLooper.cpp",
   "$_src/core/SkDeviceProfile.cpp",
   "$_src/core/SkDiscardableMemory.h",
@@ -381,7 +383,6 @@ skia_core_sources = [
 
   "$_include/core/SkBBHFactory.h",
   "$_include/core/SkBitmap.h",
-  "$_include/core/SkBitmapDevice.h",
   "$_include/core/SkCanvas.h",
   "$_include/core/SkClipStack.h",
   "$_include/core/SkColor.h",
@@ -389,7 +390,6 @@ skia_core_sources = [
   "$_include/core/SkColorPriv.h",
   "$_include/core/SkData.h",
   "$_include/core/SkDeque.h",
-  "$_include/core/SkDevice.h",
   "$_include/core/SkDrawable.h",
   "$_include/core/SkDrawFilter.h",
   "$_include/core/SkDrawLooper.h",