Revert of Fix colorType/alphaType checks in SkCodec

src/codec/SkWbmpCodec.cpp

Index: src/codec/SkWbmpCodec.cpp
diff --git a/src/codec/SkWbmpCodec.cpp b/src/codec/SkWbmpCodec.cpp
index dd6699473040bed3fd79001321a8d28299dc48ff..4dd0f2544d181f848dde3b0cf015967e69f12518 100644
--- a/src/codec/SkWbmpCodec.cpp
+++ b/src/codec/SkWbmpCodec.cpp
@@ -27,19 +27,6 @@
         colorPtr[0] = SK_ColorBLACK;
         colorPtr[1] = SK_ColorWHITE;
         *colorCount = 2;
-    }
-}
-
-static inline bool valid_color_type(SkColorType colorType, SkAlphaType alphaType) {
-    switch (colorType) {
-        case kN32_SkColorType:
-        case kIndex_8_SkColorType:
-            return true;
-        case kGray_8_SkColorType:
-        case kRGB_565_SkColorType:
-            return kOpaque_SkAlphaType == alphaType;
-        default:
-            return false;
     }
 }
 
@@ -97,6 +84,16 @@
 
 SkSwizzler* SkWbmpCodec::initializeSwizzler(const SkImageInfo& info, const SkPMColor* ctable,
         const Options& opts) {
+    // Create the swizzler based on the desired color type
+    switch (info.colorType()) {
+        case kIndex_8_SkColorType:
+        case kN32_SkColorType:
+        case kRGB_565_SkColorType:
+        case kGray_8_SkColorType:
+            break;
+        default:
+            return nullptr;
+    }
     return SkSwizzler::CreateSwizzler(SkSwizzler::kBit, ctable, info, opts);
 }
 
@@ -127,8 +124,7 @@
         return kUnimplemented;
     }
 
-    if (!valid_color_type(info.colorType(), info.alphaType()) ||
-            !valid_alpha(info.alphaType(), this->getInfo().alphaType())) {
+    if (!valid_alpha(info.alphaType(), this->getInfo().alphaType())) {
         return kInvalidConversion;
     }
 
@@ -137,7 +133,9 @@
 
     // Initialize the swizzler
     SkAutoTDelete<SkSwizzler> swizzler(this->initializeSwizzler(info, ctable, options));
-    SkASSERT(swizzler);
+    if (nullptr == swizzler.get()) {
+        return kInvalidConversion;
+    }
 
     // Perform the decode
     SkISize size = info.dimensions();
@@ -190,8 +188,7 @@
         return kUnimplemented;
     }
 
-    if (!valid_color_type(dstInfo.colorType(), dstInfo.alphaType()) ||
-            !valid_alpha(dstInfo.alphaType(), this->getInfo().alphaType())) {
+    if (!valid_alpha(dstInfo.alphaType(), this->getInfo().alphaType())) {
         return kInvalidConversion;
     }
 
@@ -205,7 +202,9 @@
 
     // Initialize the swizzler
     fSwizzler.reset(this->initializeSwizzler(dstInfo, get_color_ptr(fColorTable.get()), options));
-    SkASSERT(fSwizzler);
+    if (nullptr == fSwizzler.get()) {
+        return kInvalidConversion;
+    }
 
     fSrcBuffer.reset(fSrcRowBytes);