LibGfx: Remove Gfx::ImageDecoder::bitmap() in favor of frame(index)

To transparently support multi-frame images, all decoder plugins have
already been updated to return their only bitmap for frame(0).

This patch completes the remaining cleanup work by removing the
ImageDecoder::bitmap() API and having all clients call frame() instead.

Userland/Libraries/LibGfx/BMPLoader.cpp

@@ -1397,7 +1397,8 @@ size_t BMPImageDecoderPlugin::frame_count()
 ImageFrameDescriptor BMPImageDecoderPlugin::frame(size_t i)
 {
     if (i > 0)
-        return { bitmap(), 0 };
-    return {};
+        return {};
+    return { bitmap(), 0 };
 }
+
 }

Userland/Libraries/LibGfx/DDSLoader.cpp

@@ -1046,9 +1046,11 @@ size_t DDSImageDecoderPlugin::frame_count()
     return 1;
 }
 
-ImageFrameDescriptor DDSImageDecoderPlugin::frame([[maybe_unused]] size_t i)
+ImageFrameDescriptor DDSImageDecoderPlugin::frame(size_t i)
 {
-    // We have "frames", but they are all the same image, so lets just use the largest version.
+    if (i > 0)
+        return {};
     return { bitmap(), 0 };
 }
+
 }

Userland/Libraries/LibGfx/ICOLoader.cpp

@@ -382,10 +382,9 @@ size_t ICOImageDecoderPlugin::frame_count()
 
 ImageFrameDescriptor ICOImageDecoderPlugin::frame(size_t i)
 {
-    if (i > 0) {
-        return { bitmap(), 0 };
-    }
-    return {};
+    if (i > 0)
+        return {};
+    return { bitmap(), 0 };
 }
 
 }

Userland/Libraries/LibGfx/ImageDecoder.cpp

@@ -78,9 +78,4 @@ ImageDecoder::~ImageDecoder()
 {
 }
 
-RefPtr<Gfx::Bitmap> ImageDecoder::bitmap() const
-{
-    return m_plugin->bitmap();
-}
-
 }

Userland/Libraries/LibGfx/ImageDecoder.h

@@ -30,7 +30,6 @@ public:
     virtual ~ImageDecoderPlugin() { }
 
     virtual IntSize size() = 0;
-    virtual RefPtr<Gfx::Bitmap> bitmap() = 0;
 
     virtual void set_volatile() = 0;
     [[nodiscard]] virtual bool set_nonvolatile(bool& was_purged) = 0;
@@ -43,6 +42,8 @@ public:
     virtual ImageFrameDescriptor frame(size_t i) = 0;
 
 protected:
+    virtual RefPtr<Gfx::Bitmap> bitmap() = 0;
+
     ImageDecoderPlugin() { }
 };
 
@@ -54,7 +55,6 @@ public:
     IntSize size() const { return m_plugin->size(); }
     int width() const { return size().width(); }
     int height() const { return size().height(); }
-    RefPtr<Gfx::Bitmap> bitmap() const;
     void set_volatile() { m_plugin->set_volatile(); }
     [[nodiscard]] bool set_nonvolatile(bool& was_purged) { return m_plugin->set_nonvolatile(was_purged); }
     bool sniff() const { return m_plugin->sniff(); }

Userland/Libraries/LibGfx/JPGLoader.cpp

@@ -1327,9 +1327,9 @@ size_t JPGImageDecoderPlugin::frame_count()
 
 ImageFrameDescriptor JPGImageDecoderPlugin::frame(size_t i)
 {
-    if (i > 0) {
-        return { bitmap(), 0 };
-    }
-    return {};
+    if (i > 0)
+        return {};
+    return { bitmap(), 0 };
 }
+
 }

Userland/Libraries/LibGfx/PBMLoader.cpp

@@ -195,11 +195,9 @@ size_t PBMImageDecoderPlugin::frame_count()
 
 ImageFrameDescriptor PBMImageDecoderPlugin::frame(size_t i)
 {
-    if (i > 0) {
-        return { bitmap(), 0 };
-    }
-
-    return {};
+    if (i > 0)
+        return {};
+    return { bitmap(), 0 };
 }
 
 }

Userland/Libraries/LibGfx/PGMLoader.cpp

@@ -198,11 +198,9 @@ size_t PGMImageDecoderPlugin::frame_count()
 
 ImageFrameDescriptor PGMImageDecoderPlugin::frame(size_t i)
 {
-    if (i > 0) {
-        return { bitmap(), 0 };
-    }
-
-    return {};
+    if (i > 0)
+        return {};
+    return { bitmap(), 0 };
 }
 
 }

Userland/Libraries/LibGfx/PNGLoader.cpp

@@ -1013,10 +1013,9 @@ size_t PNGImageDecoderPlugin::frame_count()
 
 ImageFrameDescriptor PNGImageDecoderPlugin::frame(size_t i)
 {
-    if (i > 0) {
-        return { bitmap(), 0 };
-    }
-    return {};
+    if (i > 0)
+        return {};
+    return { bitmap(), 0 };
 }
 
 }

Userland/Libraries/LibGfx/PPMLoader.cpp

@@ -200,11 +200,9 @@ size_t PPMImageDecoderPlugin::frame_count()
 
 ImageFrameDescriptor PPMImageDecoderPlugin::frame(size_t i)
 {
-    if (i > 0) {
-        return { bitmap(), 0 };
-    }
-
-    return {};
+    if (i > 0)
+        return {};
+    return { bitmap(), 0 };
 }
 
 }