Add SkEncodedOrigin to SkYUVASizeInfo, fix JPEG orientation in GPU decode path

Bug: skia:7523
Change-Id: I7d48e5f5930b413fa7f27aa391bf92c5af1342e9
Reviewed-on: https://skia-review.googlesource.com/c/173429
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
diff --git a/include/codec/SkEncodedOrigin.h b/include/codec/SkEncodedOrigin.h
index 622ade1..89ed9bb 100644
--- a/include/codec/SkEncodedOrigin.h
+++ b/include/codec/SkEncodedOrigin.h
@@ -7,6 +7,9 @@
 
 #ifndef SkEncodedOrigin_DEFINED
 #define SkEncodedOrigin_DEFINED
+
+#include "SkMatrix.h"
+
 // These values match the orientation www.exif.org/Exif2-2.PDF.
 enum SkEncodedOrigin {
     kTopLeft_SkEncodedOrigin     = 1, // Default
@@ -20,4 +23,26 @@
     kDefault_SkEncodedOrigin     = kTopLeft_SkEncodedOrigin,
     kLast_SkEncodedOrigin        = kLeftBottom_SkEncodedOrigin,
 };
+
+/**
+ * Given an encoded origin and the width and height of the source data, returns a matrix
+ * that transforms the source rectangle [0, 0, w, h] to a correctly oriented destination
+ * rectangle, with the upper left corner still at [0, 0].
+ */
+static inline SkMatrix SkEncodedOriginToMatrix(SkEncodedOrigin origin, int w, int h) {
+    switch (origin) {
+        case     kTopLeft_SkEncodedOrigin: return SkMatrix::I();
+        case    kTopRight_SkEncodedOrigin: return SkMatrix::MakeAll(-1,  0, w,  0,  1, 0, 0, 0, 1);
+        case kBottomRight_SkEncodedOrigin: return SkMatrix::MakeAll(-1,  0, w,  0, -1, h, 0, 0, 1);
+        case  kBottomLeft_SkEncodedOrigin: return SkMatrix::MakeAll( 1,  0, 0,  0, -1, h, 0, 0, 1);
+        case     kLeftTop_SkEncodedOrigin: return SkMatrix::MakeAll( 0,  1, 0,  1,  0, 0, 0, 0, 1);
+        case    kRightTop_SkEncodedOrigin: return SkMatrix::MakeAll( 0, -1, h,  1,  0, 0, 0, 0, 1);
+        case kRightBottom_SkEncodedOrigin: return SkMatrix::MakeAll( 0, -1, h, -1,  0, w, 0, 0, 1);
+        case  kLeftBottom_SkEncodedOrigin: return SkMatrix::MakeAll( 0,  1, 0, -1,  0, w, 0, 0, 1);
+    }
+    SK_ABORT("Unexpected origin");
+    return SkMatrix::I();
+}
+
+
 #endif // SkEncodedOrigin_DEFINED