Revert of Delete SkFlattenable::Type (patchset #2 id:20001 of https://codereview.chromium.org/1834303003/ )

Reason for revert:
Used by Chrome.

c:\b\build\slave\workdir\build\src\cc\playback\compositing_display_item.cc(53): error C2039: 'GetFlattenableType': is not a member of 'SkColorFilter'
c:\b\build\slave\workdir\build\src\third_party\skia\include\core\skshader.h(19): note: see declaration of 'SkColorFilter'
c:\b\build\slave\workdir\build\src\cc\playback\compositing_display_item.cc(53): error C3861: 'GetFlattenableType': identifier not found

Original issue's description:
> Delete SkFlattenable::Type
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1834303003
>
> Committed: https://skia.googlesource.com/skia/+/99d9231f6a4cb6b85b8637e9d8ae32f8bd7c466f

TBR=reed@google.com,msarett@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1853383002

8 files changed, 47 insertions, 13 deletions

diff --git a/src/core/SkFlattenable.cpp b/src/core/SkFlattenable.cpp
index 506a7b14e7..c759a1ab38 100644
--- a/src/core/SkFlattenable.cpp
+++ b/src/core/SkFlattenable.cpp
@@ -53,18 +53,20 @@ void SkRefCntSet::decPtr(void* ptr) {
 struct Entry {
     const char*             fName;
     SkFlattenable::Factory  fFactory;
+    SkFlattenable::Type     fType;
 };
 
 static int gCount = 0;
 static Entry gEntries[MAX_ENTRY_COUNT];
 
-void SkFlattenable::Register(const char name[], Factory factory) {
+void SkFlattenable::Register(const char name[], Factory factory, SkFlattenable::Type type) {
     SkASSERT(name);
     SkASSERT(factory);
     SkASSERT(gCount < MAX_ENTRY_COUNT);
 
     gEntries[gCount].fName = name;
     gEntries[gCount].fFactory = factory;
+    gEntries[gCount].fType = type;
     gCount += 1;
 }
 
@@ -92,6 +94,22 @@ SkFlattenable::Factory SkFlattenable::NameToFactory(const char name[]) {
     return nullptr;
 }
 
+bool SkFlattenable::NameToType(const char name[], SkFlattenable::Type* type) {
+    SkASSERT(type);
+    InitializeFlattenablesIfNeeded();
+#ifdef SK_DEBUG
+    report_no_entries(__FUNCTION__);
+#endif
+    const Entry* entries = gEntries;
+    for (int i = gCount - 1; i >= 0; --i) {
+        if (strcmp(entries[i].fName, name) == 0) {
+            *type = entries[i].fType;
+            return true;
+        }
+    }
+    return false;
+}
+
 const char* SkFlattenable::FactoryToName(Factory fact) {
     InitializeFlattenablesIfNeeded();
 #ifdef SK_DEBUG
diff --git a/src/core/SkFlattenableSerialization.cpp b/src/core/SkFlattenableSerialization.cpp
index 748e20a9c2..e9ce09ff1f 100644
--- a/src/core/SkFlattenableSerialization.cpp
+++ b/src/core/SkFlattenableSerialization.cpp
@@ -20,7 +20,8 @@ SkData* SkValidatingSerializeFlattenable(SkFlattenable* flattenable) {
     return data.release();
 }
 
-SkFlattenable* SkValidatingDeserializeFlattenable(const void* data, size_t size) {
+SkFlattenable* SkValidatingDeserializeFlattenable(const void* data, size_t size,
+                                                  SkFlattenable::Type type) {
     SkValidatingReadBuffer buffer(data, size);
-    return buffer.readFlattenable();
+    return buffer.readFlattenable(type);
 }
diff --git a/src/core/SkReadBuffer.cpp b/src/core/SkReadBuffer.cpp
index d57b223700..f220b5a9e6 100644
--- a/src/core/SkReadBuffer.cpp
+++ b/src/core/SkReadBuffer.cpp
@@ -329,7 +329,11 @@ SkTypeface* SkReadBuffer::readTypeface() {
     }
 }
 
-SkFlattenable* SkReadBuffer::readFlattenable() {
+SkFlattenable* SkReadBuffer::readFlattenable(SkFlattenable::Type ft) {
+    //
+    // TODO: confirm that ft matches the factory we decide to use
+    //
+
     SkFlattenable::Factory factory = nullptr;
 
     if (fFactoryCount > 0) {
diff --git a/src/core/SkReadBuffer.h b/src/core/SkReadBuffer.h
index cd570e18f3..7b12194fc0 100644
--- a/src/core/SkReadBuffer.h
+++ b/src/core/SkReadBuffer.h
@@ -126,9 +126,9 @@ public:
     virtual void readPath(SkPath* path);
     void readPaint(SkPaint* paint) { paint->unflatten(*this); }
 
-    virtual SkFlattenable* readFlattenable();
+    virtual SkFlattenable* readFlattenable(SkFlattenable::Type);
     template <typename T> sk_sp<T> readFlattenable() {
-        return sk_sp<T>((T*)this->readFlattenable());
+        return sk_sp<T>((T*)this->readFlattenable(T::GetFlattenableType()));
     }
     sk_sp<SkColorFilter> readColorFilter() { return this->readFlattenable<SkColorFilter>(); }
     sk_sp<SkDrawLooper> readDrawLooper() { return this->readFlattenable<SkDrawLooper>(); }
diff --git a/src/core/SkScalerContext.cpp b/src/core/SkScalerContext.cpp
index 3db9e30876..cf4098bbdd 100644
--- a/src/core/SkScalerContext.cpp
+++ b/src/core/SkScalerContext.cpp
@@ -62,14 +62,15 @@ void SkGlyph::zeroMetrics() {
     #define DUMP_RECx
 #endif
 
-static SkFlattenable* load_flattenable(const SkDescriptor* desc, uint32_t tag) {
+static SkFlattenable* load_flattenable(const SkDescriptor* desc, uint32_t tag,
+                                       SkFlattenable::Type ft) {
     SkFlattenable*  obj = nullptr;
     uint32_t        len;
     const void*     data = desc->findEntry(tag, &len);
 
     if (data) {
         SkReadBuffer buffer(data, len);
-        obj = buffer.readFlattenable();
+        obj = buffer.readFlattenable(ft);
         SkASSERT(buffer.offset() == buffer.size());
     }
     return obj;
@@ -79,9 +80,12 @@ SkScalerContext::SkScalerContext(SkTypeface* typeface, const SkDescriptor* desc)
     : fRec(*static_cast<const Rec*>(desc->findEntry(kRec_SkDescriptorTag, nullptr)))
 
     , fTypeface(SkRef(typeface))
-    , fPathEffect(static_cast<SkPathEffect*>(load_flattenable(desc, kPathEffect_SkDescriptorTag)))
-    , fMaskFilter(static_cast<SkMaskFilter*>(load_flattenable(desc, kMaskFilter_SkDescriptorTag)))
-    , fRasterizer(static_cast<SkRasterizer*>(load_flattenable(desc, kRasterizer_SkDescriptorTag)))
+    , fPathEffect(static_cast<SkPathEffect*>(load_flattenable(desc, kPathEffect_SkDescriptorTag,
+                                             SkFlattenable::kSkPathEffect_Type)))
+    , fMaskFilter(static_cast<SkMaskFilter*>(load_flattenable(desc, kMaskFilter_SkDescriptorTag,
+                                             SkFlattenable::kSkMaskFilter_Type)))
+    , fRasterizer(static_cast<SkRasterizer*>(load_flattenable(desc, kRasterizer_SkDescriptorTag,
+                                             SkFlattenable::kSkRasterizer_Type)))
       // Initialize based on our settings. Subclasses can also force this.
     , fGenerateImageFromPath(fRec.fFrameWidth > 0 || fPathEffect != nullptr || fRasterizer != nullptr)
 
diff --git a/src/core/SkValidatingReadBuffer.cpp b/src/core/SkValidatingReadBuffer.cpp
index 0ce8bf9c59..ad4b6c409e 100644
--- a/src/core/SkValidatingReadBuffer.cpp
+++ b/src/core/SkValidatingReadBuffer.cpp
@@ -222,14 +222,20 @@ bool SkValidatingReadBuffer::validateAvailable(size_t size) {
     return this->validate((size <= SK_MaxU32) && fReader.isAvailable(static_cast<uint32_t>(size)));
 }
 
-SkFlattenable* SkValidatingReadBuffer::readFlattenable() {
+SkFlattenable* SkValidatingReadBuffer::readFlattenable(SkFlattenable::Type type) {
     SkString name;
     this->readString(&name);
     if (fError) {
         return nullptr;
     }
 
+    // Is this the type we wanted ?
     const char* cname = name.c_str();
+    SkFlattenable::Type baseType;
+    if (!SkFlattenable::NameToType(cname, &baseType) || (baseType != type)) {
+        return nullptr;
+    }
+
     SkFlattenable::Factory factory = SkFlattenable::NameToFactory(cname);
     if (nullptr == factory) {
         return nullptr; // writer failed to give us the flattenable
diff --git a/src/core/SkValidatingReadBuffer.h b/src/core/SkValidatingReadBuffer.h
index 4b8cdf88c0..bcdcba5de4 100644
--- a/src/core/SkValidatingReadBuffer.h
+++ b/src/core/SkValidatingReadBuffer.h
@@ -39,7 +39,7 @@ public:
     void* readEncodedString(size_t* length, SkPaint::TextEncoding encoding) override;
 
     // common data structures
-    SkFlattenable* readFlattenable() override;
+    SkFlattenable* readFlattenable(SkFlattenable::Type type) override;
     void skipFlattenable() override;
     void readPoint(SkPoint* point) override;
     void readMatrix(SkMatrix* matrix) override;
diff --git a/src/utils/SkBitmapSourceDeserializer.h b/src/utils/SkBitmapSourceDeserializer.h
index 60f185e17a..e017599918 100644
--- a/src/utils/SkBitmapSourceDeserializer.h
+++ b/src/utils/SkBitmapSourceDeserializer.h
@@ -14,6 +14,7 @@
 // Should be removed when SKP versions which may contain SkBitmapSource records are phased out.
 class SkBitmapSourceDeserializer : public SkFlattenable {
 public:
+    SK_DEFINE_FLATTENABLE_TYPE(SkImageFilter)
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkBitmapSource)
 };