Cleanup old/deprecated wire and native APIs

Bug: none
Change-Id: Idf9a00d8dc675e1fbc83554c487edcb2dda498c8
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/30001
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>

src/include/dawn_native/DawnNative.h

@@ -215,10 +215,7 @@ namespace dawn_native {
       public:
         const ExternalImageType type;
         const WGPUTextureDescriptor* cTextureDescriptor;  // Must match image creation params
-        union {
-            bool isInitialized;  // Whether the texture is initialized on import
-            bool isCleared;      // DEPRECATED: Sets whether the texture will be cleared before use
-        };
+        bool isInitialized;  // Whether the texture is initialized on import
 
       protected:
         ExternalImageDescriptor(ExternalImageType type);

src/include/dawn_wire/Wire.h

@@ -33,11 +33,7 @@ namespace dawn_wire {
         // a fatal error.
         virtual void* GetCmdSpace(size_t size) = 0;
         virtual bool Flush() = 0;
-
-        // TODO(enga): Make pure virtual after updating Chromium.
-        virtual size_t GetMaximumAllocationSize() const {
-            return std::numeric_limits<size_t>::max();
-        }
+        virtual size_t GetMaximumAllocationSize() const = 0;
     };
 
     class DAWN_WIRE_EXPORT CommandHandler {

src/include/dawn_wire/WireClient.h

@@ -46,9 +46,6 @@ namespace dawn_wire {
         WireClient(const WireClientDescriptor& descriptor);
         ~WireClient() override;
 
-        // TODO(enga): Remove this and use dawn_wire::client::GetProcs() instead
-        static const DawnProcTable& GetProcs();
-
         WGPUDevice GetDevice() const;
         const volatile char* HandleCommands(const volatile char* commands,
                                             size_t size) override final;