Add buffer helper to read directly into SkString to avoid extra copying

src/core/SkOrderedReadBuffer.cpp

Index: src/core/SkOrderedReadBuffer.cpp
diff --git a/src/core/SkOrderedReadBuffer.cpp b/src/core/SkOrderedReadBuffer.cpp
index 85491c5607545b04f8c48652399a611b3524cd21..1e7990c66af1811236a435b21bc1d2e5bd536ef7 100644
--- a/src/core/SkOrderedReadBuffer.cpp
+++ b/src/core/SkOrderedReadBuffer.cpp
@@ -88,9 +88,14 @@ int32_t SkOrderedReadBuffer::read32() {
     return fReader.readInt();
 }
 
+void SkOrderedReadBuffer::readString(SkString& string) {
+    size_t len;
+    string.set(fReader.readString(&len), len);

[reed1, 2013/05/20 13:42:47]

Parameter evaluation order is undefined, so it is possible that the 2nd arg will
be evaluated first, passing an uninitialized value for len. Probably should use
the same pattern as we do below in readString().

[djsollen, 2013/05/21 12:17:17]

Done.

+}
+
 char* SkOrderedReadBuffer::readString() {

[reed1, 2013/05/20 13:42:47]

Suggestion: rename this to something other than String, indicating that it was
allocated via malloc.

e.g.
readCString
readCStringWithMalloc

... do we even need it, how that you're adding a cool version of readString?

[djsollen, 2013/05/21 12:17:17]

removed and updated the one caller to use the new readString call.

On 2013/05/20 13:42:47, reed1 wrote:

-    const char* string = fReader.readString();
-    const size_t length = strlen(string);
+    size_t length;
+    const char* string = fReader.readString(&length);
     char* value = (char*)sk_malloc_throw(length + 1);
     strcpy(value, string);
     return value;