Serializes GL context states and reformats frame_capture_utils

Adds the ability to serialize GL context states.
Adds serialization of GL context states to serializeContext method so
that capture replay regression testing now compares the GL context
states.

Reformats frame_capture_utils to make most serialization methods
private, except for the ones called by other classes and template
methods.

Bug: angleproject:4817
Change-Id: I2d53c88be3d503268bd6e2e5058b5fabe0644f67
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2314829
Commit-Queue: Manh Nguyen <nguyenmh@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Cody Northrop <cnorthrop@google.com>

Author: Manh Nguyen

src/libANGLE/State.h

@@ -68,6 +68,7 @@ using SamplerBindingVector = std::vector<BindingPointer<Sampler>>;
 using TextureBindingVector = std::vector<BindingPointer<Texture>>;
 using TextureBindingMap    = angle::PackedEnumMap<TextureType, TextureBindingVector>;
 using ActiveQueryMap       = angle::PackedEnumMap<QueryType, BindingPointer<Query>>;
+using BufferVector         = std::vector<OffsetBindingPointer<Buffer>>;
 
 class ActiveTexturesCache final : angle::NonCopyable
 {
@@ -232,6 +233,10 @@ class State : angle::NonCopyable
         ASSERT(maskNumber < mMaxSampleMaskWords);
         return mSampleMaskValues[maskNumber];
     }
+    std::array<GLbitfield, MAX_SAMPLE_MASK_WORDS> getSampleMaskValues() const
+    {
+        return mSampleMaskValues;
+    }
     GLuint getMaxSampleMaskWords() const { return mMaxSampleMaskWords; }
 
     // Multisampling/alpha to one manipulation.
@@ -265,6 +270,7 @@ class State : angle::NonCopyable
     GLenum getGenerateMipmapHint() const;
     void setTextureFilteringHint(GLenum hint);
     GLenum getTextureFilteringHint() const;
+    GLenum getFragmentShaderDerivativeHint() const { return mFragmentShaderDerivativeHint; }
     void setFragmentShaderDerivativeHint(GLenum hint);
 
     // GL_CHROMIUM_bind_generates_resource
@@ -796,6 +802,39 @@ class State : angle::NonCopyable
 
     bool isEarlyFragmentTestsOptimizationAllowed() const { return isSampleCoverageEnabled(); }
 
+    const BufferVector &getOffsetBindingPointerUniformBuffers() const { return mUniformBuffers; }
+
+    const BufferVector &getOffsetBindingPointerAtomicCounterBuffers() const
+    {
+        return mAtomicCounterBuffers;
+    }
+
+    const BufferVector &getOffsetBindingPointerShaderStorageBuffers() const
+    {
+        return mShaderStorageBuffers;
+    }
+
+    ActiveTextureMask getTexturesIncompatibleWithSamplers() const
+    {
+        return mTexturesIncompatibleWithSamplers;
+    }
+
+    bool isProgramBinaryCacheEnabled() const { return mProgramBinaryCacheEnabled; }
+
+    bool isTextureRectangleEnabled() const { return mTextureRectangleEnabled; }
+
+    DrawBufferMask getBlendFuncConstantAlphaDrawBuffers() const
+    {
+        return mBlendFuncConstantAlphaDrawBuffers;
+    }
+
+    DrawBufferMask getBlendFuncConstantColorDrawBuffers() const
+    {
+        return mBlendFuncConstantColorDrawBuffers;
+    }
+
+    const std::vector<ImageUnit> getImageUnits() const { return mImageUnits; }
+
     const BlendStateExt &getBlendStateExt() const { return mBlendStateExt; }
 
   private:
@@ -973,7 +1012,6 @@ class State : angle::NonCopyable
     // vertex array object.
     BoundBufferMap mBoundBuffers;
 
-    using BufferVector = std::vector<OffsetBindingPointer<Buffer>>;
     BufferVector mUniformBuffers;
     BufferVector mAtomicCounterBuffers;
     BufferVector mShaderStorageBuffers;