Fix color xforms for Index8 bmps

Thanks to Gold for catching this.

BUG=skia:4895

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4426

Change-Id: Icc816d933e9e2fd312858a5430fa21a47722563e
Reviewed-on: https://skia-review.googlesource.com/4426
Commit-Queue: Matt Sarett <msarett@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/codec/SkBmpRLECodec.cpp b/src/codec/SkBmpRLECodec.cpp
index 85b965e611..b8013093fb 100644
--- a/src/codec/SkBmpRLECodec.cpp
+++ b/src/codec/SkBmpRLECodec.cpp
@@ -276,9 +276,16 @@ SkCodec::Result SkBmpRLECodec::onPrepareToDecode(const SkImageInfo& dstInfo,
     fSampleX = 1;
     fLinesToSkip = 0;
 
+    SkColorType colorTableColorType = dstInfo.colorType();
+    if (this->colorXform()) {
+        // Just set a known colorType for the colorTable.  No need to actually transform
+        // the colors in the colorTable since we do not allow decoding RLE to kIndex8.
+        colorTableColorType = kBGRA_8888_SkColorType;
+    }
+
     // Create the color table if necessary and prepare the stream for decode
     // Note that if it is non-NULL, inputColorCount will be modified
-    if (!this->createColorTable(dstInfo.colorType(), inputColorCount)) {
+    if (!this->createColorTable(colorTableColorType, inputColorCount)) {
         SkCodecPrintf("Error: could not create color table.\n");
         return SkCodec::kInvalidInput;
     }