Added a Uuid::null variable.

modules/juce_core/misc/juce_Uuid.cpp

@@ -51,6 +51,8 @@ Uuid& Uuid::operator= (const Uuid& other) noexcept
 bool Uuid::operator== (const Uuid& other) const noexcept    { return memcmp (uuid, other.uuid, sizeof (uuid)) == 0; }
 bool Uuid::operator!= (const Uuid& other) const noexcept    { return ! operator== (other); }
 
+Uuid Uuid::null ((const uint8*) nullptr);
+
 bool Uuid::isNull() const noexcept
 {
     for (size_t i = 0; i < sizeof (uuid); ++i)

modules/juce_core/misc/juce_Uuid.h

@@ -60,6 +60,9 @@ public:
     /** Returns true if the ID is zero. */
     bool isNull() const noexcept;
 
+    /** A static null Uuid object. */
+    static Uuid null;
+
     bool operator== (const Uuid& other) const noexcept;
     bool operator!= (const Uuid& other) const noexcept;