Remove uses of SkImageDecoder from skdiff

tools/skdiff_main.cpp

Index: tools/skdiff_main.cpp
diff --git a/tools/skdiff_main.cpp b/tools/skdiff_main.cpp
index 0dca407bf01fd9237f971e64e1788e16b19d1301..8b56ea5f8ecc8e844ae5dfbf17a039db494b4055 100644
--- a/tools/skdiff_main.cpp
+++ b/tools/skdiff_main.cpp
@@ -10,7 +10,6 @@
 #include "SkBitmap.h"
 #include "SkData.h"
 #include "SkForceLinking.h"

[scroggo, 2016/03/11 19:56:13]

I assume this is no longer necessary

[msarett, 2016/03/11 19:58:08]

I recently realized that force linking is also used by SkImageEncoder.

I'm not 100% sure, but this could potentially be required for uses of
SkImageEncoder in this file.

[scroggo, 2016/03/11 20:00:34]

Really? I added force linking because we auto-register our image decoders. For
encoding, we call them directly, so the linker shouldn't be stripping them.

[msarett, 2016/03/11 20:05:47]

Maybe I'm wrong...  I'm certainly not an expert in force linking.

I'm basing this on:
https://codereview.chromium.org/1777753002/

Before Patch Set 2, the encode step would fail without even trying to create a
PNG encoder.
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/skia/s...

-#include "SkImageDecoder.h"
 #include "SkImageEncoder.h"
 #include "SkOSFile.h"
 #include "SkStream.h"
@@ -349,7 +348,7 @@ static void get_bounds(DiffResource& resource, const char* name) {
             SkDebugf("WARNING: couldn't read %s file <%s>\n", name, resource.fFullPath.c_str());
             resource.fStatus = DiffResource::kCouldNotRead_Status;
         } else {
-            get_bitmap(fileBits, resource, SkImageDecoder::kDecodeBounds_Mode);
+            get_bitmap(fileBits, resource, true);
         }
     }
 }
@@ -493,9 +492,8 @@ static void create_diff_images (DiffMetricProc dmp,
                 VERBOSE_STATUS("MATCH", ANSI_COLOR_GREEN, baseFiles[i]);
             } else {
                 AutoReleasePixels arp(drp);
-                get_bitmap(baseFileBits, drp->fBase, SkImageDecoder::kDecodePixels_Mode);
-                get_bitmap(comparisonFileBits, drp->fComparison,
-                           SkImageDecoder::kDecodePixels_Mode);
+                get_bitmap(baseFileBits, drp->fBase, false);
+                get_bitmap(comparisonFileBits, drp->fComparison, false);
                 VERBOSE_STATUS("DIFFERENT", ANSI_COLOR_RED, baseFiles[i]);
                 if (DiffResource::kDecoded_Status == drp->fBase.fStatus &&
                     DiffResource::kDecoded_Status == drp->fComparison.fStatus) {