Down-integrate from internal branch
diff --git a/CHANGES.txt b/CHANGES.txt
index 737f865..a21e956 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,3 +1,61 @@
+2012-09-19 version 2.5.0:
+
+ General
+ * New notion "import public" that allows a proto file to forward the content
+ it imports to its importers. For example,
+ // foo.proto
+ import public "bar.proto";
+ import "baz.proto";
+
+ // qux.proto
+ import "foo.proto";
+ // Stuff defined in bar.proto may be used in this file, but stuff from
+ // baz.proto may NOT be used without importing it explicitly.
+ This is useful for moving proto files. To move a proto file, just leave
+ a single "import public" in the old proto file.
+ * New enum option "allow_alias" that specifies whether different symbols can
+ be assigned the same numeric value. Default value is "true". Setting it to
+ false causes the compiler to reject enum definitions where multiple symbols
+ have the same numeric value.
+
+ C++
+ * New generated method set_allocated_foo(Type* foo) for message and string
+ fields. This method allows you to set the field to a pre-allocated object
+ and the containing message takes the ownership of that object.
+ * Added SetAllocatedExtension() and ReleaseExtension() to extensions API.
+ * Custom options are now formatted correctly when descriptors are printed in
+ text format.
+ * Various speed optimizations.
+
+ Java
+ * Comments in proto files are now collected and put into generated code as
+ comments for corresponding classes and data members.
+ * Added Parser to parse directly into messages without a Builder. For
+ example,
+ Foo foo = Foo.getParser().ParseFrom(input);
+ Using Parser is ~25% faster than using Builder to parse messages.
+ * Added getters/setters to access the underlying ByteString of a string field
+ directly.
+ * ByteString now supports more operations: substring(), prepend(), and
+ append(). The implementation of ByteString uses a binary tree structure
+ to support these operations efficiently.
+ * New method findInitializationErrors() that lists all missing required
+ fields.
+ * Various code size and speed optimizations.
+
+ Python
+ * Added support for dynamic message creation. DescriptorDatabase,
+ DescriptorPool, and MessageFactory work like their C++ couterparts to
+ simplify Descriptor construction from *DescriptorProtos, and MessageFactory
+ provides a message instance from a Descriptor.
+ * Added pickle support for protobuf messages.
+ * Unknown fields are now preserved after parsing.
+ * Fixed bug where custom options were not correctly populated. Custom
+ options can be accessed now.
+ * Added EnumTypeWrapper that provides better accessibility to enum types.
+ * Added ParseMessage(descriptor, bytes) to generate a new Message instance
+ from a descriptor and a byte string.
+
2011-05-01 version 2.4.1:
C++