Attempt 3: SkRasterPipelineBlitter: support A8

Now that SkOpts_hsw.cpp no longer hooks in SkRasterPipeline_opts,
it should be safe to try this again.

This reverts commit 86d55b312a2649d80890ccf75f24571ada0265f1.

Change-Id: I2d495600ca9d3a0f49c2e02fbaaae349cefac3a1
Reviewed-on: https://skia-review.googlesource.com/6985
Reviewed-by: Mike Klein <mtklein@chromium.org>

1 files changed, 8 insertions, 5 deletions

diff --git a/src/core/SkBlitter.cpp b/src/core/SkBlitter.cpp
index c97956c20f..86c49d08ae 100644
--- a/src/core/SkBlitter.cpp
+++ b/src/core/SkBlitter.cpp
@@ -857,6 +857,12 @@ SkBlitter* SkBlitter::Choose(const SkPixmap& device,
         p->setColor(0);
     }
 
+    if (kAlpha_8_SkColorType == device.colorType() && drawCoverage) {
+        SkASSERT(nullptr == shader);
+        SkASSERT(paint->isSrcOver());
+        return allocator->createT<SkA8_Coverage_Blitter>(device, *paint);
+    }
+
     if (SkBlitter* blitter = SkCreateRasterPipelineBlitter(device, *paint, matrix, allocator)) {
         return blitter;
     }
@@ -913,11 +919,8 @@ SkBlitter* SkBlitter::Choose(const SkPixmap& device,
     SkBlitter*  blitter = nullptr;
     switch (device.colorType()) {
         case kAlpha_8_SkColorType:
-            if (drawCoverage) {
-                SkASSERT(nullptr == shader);
-                SkASSERT(paint->isSrcOver());
-                blitter = allocator->createT<SkA8_Coverage_Blitter>(device, *paint);
-            } else if (shader) {
+            SkASSERT(!drawCoverage);  // Handled above.
+            if (shader) {
                 blitter = allocator->createT<SkA8_Shader_Blitter>(device, *paint, shaderContext);
             } else {
                 blitter = allocator->createT<SkA8_Blitter>(device, *paint);