Port FlatBuffers to Go.

Implement code generation and runtime library for Go, derived from the
Java implementation. Additionally, the test suite verifies:

 - the exact bytes in the Builder buffer during object construction,
 - vtable deduplication, and
 - table construction, via a fuzzer derived from the C++ implementation.

Change-Id: Ib95a019c684891def2b50281e570b4843fea7baa

go/unsafe.go

@@ -0,0 +1,45 @@
+package flatbuffers
+
+import "unsafe"
+
+var (
+	// See http://golang.org/ref/spec#Numeric_types
+
+	// SizeUint8 is the byte size of a uint8.
+	SizeUint8 = int(unsafe.Sizeof(uint8(0)))
+	// SizeUint16 is the byte size of a uint16.
+	SizeUint16 = int(unsafe.Sizeof(uint16(0)))
+	// SizeUint32 is the byte size of a uint32.
+	SizeUint32 = int(unsafe.Sizeof(uint32(0)))
+	// SizeUint64 is the byte size of a uint64.
+	SizeUint64 = int(unsafe.Sizeof(uint64(0)))
+
+	// SizeInt8  is the byte size of a int8.
+	SizeInt8 = int(unsafe.Sizeof(int8(0)))
+	// SizeInt16 is the byte size of a int16.
+	SizeInt16 = int(unsafe.Sizeof(int16(0)))
+	// SizeInt32 is the byte size of a int32.
+	SizeInt32 = int(unsafe.Sizeof(int32(0)))
+	// SizeInt64 is the byte size of a int64.
+	SizeInt64 = int(unsafe.Sizeof(int64(0)))
+
+	// SizeFloat32 is the byte size of a float32.
+	SizeFloat32 = int(unsafe.Sizeof(float32(0)))
+	// SizeFloat64 is the byte size of a float64.
+	SizeFloat64 = int(unsafe.Sizeof(float64(0)))
+
+	// SizeByte is the byte size of a byte.
+	// The `byte` type is aliased (by Go definition) to uint8.
+	SizeByte = SizeUint8
+
+	// SizeBool is the byte size of a bool.
+	// The `bool` type is aliased (by flatbuffers convention) to uint8.
+	SizeBool = SizeUint8
+
+	// SizeSOffsetT is the byte size of an SOffsetT.
+	SizeSOffsetT = int(unsafe.Sizeof(SOffsetT(0)))
+	// SizeUOffsetT is the byte size of an UOffsetT.
+	SizeUOffsetT = int(unsafe.Sizeof(UOffsetT(0)))
+	// SizeVOffsetT is the byte size of an VOffsetT.
+	SizeVOffsetT = int(unsafe.Sizeof(VOffsetT(0)))
+)