Add ImageModel::Size().

Without this, users have to instantiate an ImageSkia just to see what
size of an image they have.

Bug: none
Change-Id: I78f07cbe04b92a62a3932432b8f73f80b7db6857
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2248891
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Auto-Submit: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#779117}

ui/base/models/image_model.cc

@@ -84,6 +84,14 @@ bool ImageModel::IsImage() const {
   return image_ && !image_.value().IsEmpty();
 }
 
+gfx::Size ImageModel::Size() const {
+  if (IsVectorIcon()) {
+    const int icon_size = GetVectorIcon().icon_size();
+    return gfx::Size(icon_size, icon_size);
+  }
+  return IsImage() ? GetImage().Size() : gfx::Size();
+}
+
 const VectorIconModel ImageModel::GetVectorIcon() const {
   DCHECK(IsVectorIcon());
   return vector_icon_model_.value();

ui/base/models/image_model.h

@@ -92,6 +92,7 @@ class COMPONENT_EXPORT(UI_BASE) ImageModel {
   bool IsEmpty() const;
   bool IsVectorIcon() const;
   bool IsImage() const;
+  gfx::Size Size() const;
   // Only valid if IsVectorIcon() or IsImage() return true, respectively.
   const VectorIconModel GetVectorIcon() const;
   const gfx::Image GetImage() const;

ui/base/models/image_model_unittest.cc

@@ -54,6 +54,14 @@ TEST(ImageModelTest, CheckForImage) {
   EXPECT_TRUE(image_model.IsImage());
 }
 
+TEST(ImageModelTest, Size) {
+  EXPECT_EQ(gfx::Size(), ImageModel().Size());
+  EXPECT_EQ(gfx::Size(16, 16),
+            ImageModel::FromVectorIcon(GetVectorIcon(), -1, 16).Size());
+  EXPECT_EQ(gfx::Size(16, 16),
+            ImageModel::FromImage(gfx::test::CreateImage(16, 16)).Size());
+}
+
 TEST(ImageModelTest, CheckAssignVectorIcon) {
   VectorIconModel vector_icon_model_dest;
   VectorIconModel vector_icon_model_src =