Add alpha type to texture producer

src/gpu/GrImageIDTextureAdjuster.cpp

Index: src/gpu/GrImageIDTextureAdjuster.cpp
diff --git a/src/gpu/GrImageIDTextureAdjuster.cpp b/src/gpu/GrImageIDTextureAdjuster.cpp
index f9aaae1282152fe69a37343e179592f52c1b00a3..5a96b6d3e6038c18b3abae52b58c9fa1a30eb23a 100644
--- a/src/gpu/GrImageIDTextureAdjuster.cpp
+++ b/src/gpu/GrImageIDTextureAdjuster.cpp
@@ -62,6 +62,10 @@ void GrBitmapTextureMaker::didCacheCopy(const GrUniqueKey& copyKey) {
     GrInstallBitmapUniqueKeyInvalidator(copyKey, fBitmap.pixelRef());
 }
 
+SkAlphaType GrBitmapTextureMaker::alphaType() const {
+    return fBitmap.alphaType();
+}
+
 SkColorSpace* GrBitmapTextureMaker::getColorSpace() {
     return fBitmap.colorSpace();
 }
@@ -101,6 +105,10 @@ void GrImageTextureMaker::didCacheCopy(const GrUniqueKey& copyKey) {
     }
 }
 
+SkAlphaType GrImageTextureMaker::alphaType() const {
+    return fCacher->info().alphaType();
+}
+
 SkColorSpace* GrImageTextureMaker::getColorSpace() {
     return fCacher->info().colorSpace();
 }