From 5cd0c28d91b88a67cfb1eba75348e8002610460d Mon Sep 17 00:00:00 2001
From: Andrew Osmond <aosmond@mozilla.com>
Date: Sat, 22 Jul 2017 07:50:32 -0400
Subject: [PATCH] Bug 1315554 - Part 8. Allow
 DecoderFactory::CreateDecoderForICOResource to create metadata decoders.
 r=tnikkel

---
 image/DecoderFactory.cpp        | 8 +++++---
 image/DecoderFactory.h          | 4 ++++
 image/decoders/nsICODecoder.cpp | 2 ++
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/image/DecoderFactory.cpp b/image/DecoderFactory.cpp
index 9570fe125f80..5dc71ab13ded 100644
--- a/image/DecoderFactory.cpp
+++ b/image/DecoderFactory.cpp
@@ -236,6 +236,7 @@ DecoderFactory::CreateMetadataDecoder(DecoderType aType,
 DecoderFactory::CreateDecoderForICOResource(DecoderType aType,
                                             SourceBufferIterator&& aIterator,
                                             NotNull<nsICODecoder*> aICODecoder,
+                                            bool aIsMetadataDecode,
                                             const Maybe<IntSize>& aExpectedSize,
                                             const Maybe<uint32_t>& aDataOffset
                                               /* = Nothing() */)
@@ -261,10 +262,11 @@ DecoderFactory::CreateDecoderForICOResource(DecoderType aType,
   MOZ_ASSERT(decoder);
 
   // Initialize the decoder, copying settings from @aICODecoder.
-  MOZ_ASSERT(!aICODecoder->IsMetadataDecode());
-  decoder->SetMetadataDecode(aICODecoder->IsMetadataDecode());
+  decoder->SetMetadataDecode(aIsMetadataDecode);
   decoder->SetIterator(Forward<SourceBufferIterator>(aIterator));
-  decoder->SetOutputSize(aICODecoder->OutputSize());
+  if (!aIsMetadataDecode) {
+    decoder->SetOutputSize(aICODecoder->OutputSize());
+  }
   if (aExpectedSize) {
     decoder->SetExpectedSize(*aExpectedSize);
   }
diff --git a/image/DecoderFactory.h b/image/DecoderFactory.h
index 0386a7b44ca0..9ce5d43192c4 100644
--- a/image/DecoderFactory.h
+++ b/image/DecoderFactory.h
@@ -127,6 +127,9 @@ public:
    *                    resource decoder, so the two decoders will have the
    *                    same decoder flags, surface flags, target size, and
    *                    other parameters.
+   * @param aIsMetadataDecode Indicates whether or not this decoder is for
+   *                          metadata or not. Independent of the state of the
+   *                          parent decoder.
    * @param aExpectedSize The expected size of the resource from the ICO header.
    * @param aDataOffset If @aType is BMP, specifies the offset at which data
    *                    begins in the BMP resource. Must be Some() if and only
@@ -136,6 +139,7 @@ public:
   CreateDecoderForICOResource(DecoderType aType,
                               SourceBufferIterator&& aIterator,
                               NotNull<nsICODecoder*> aICODecoder,
+                              bool aIsMetadataDecode,
                               const Maybe<gfx::IntSize>& aExpectedSize,
                               const Maybe<uint32_t>& aDataOffset = Nothing());
 
diff --git a/image/decoders/nsICODecoder.cpp b/image/decoders/nsICODecoder.cpp
index e0b0c08cdc89..fe5ec14bab98 100644
--- a/image/decoders/nsICODecoder.cpp
+++ b/image/decoders/nsICODecoder.cpp
@@ -277,6 +277,7 @@ nsICODecoder::SniffResource(const char* aData)
       DecoderFactory::CreateDecoderForICOResource(DecoderType::PNG,
                                                   Move(containedIterator),
                                                   WrapNotNull(this),
+                                                  false,
                                                   Some(GetRealSize()));
 
     // Read in the rest of the PNG unbuffered.
@@ -339,6 +340,7 @@ nsICODecoder::ReadBIH(const char* aData)
     DecoderFactory::CreateDecoderForICOResource(DecoderType::BMP,
                                                 Move(containedIterator),
                                                 WrapNotNull(this),
+                                                false,
                                                 Some(GetRealSize()),
                                                 Some(dataOffset));