bump SkStrAppendScalar_MaxSize to 14 to accomodate the largest string now that
scalar->string uses %.8g. Floats have at most 8 significant digits, plus we add
more space for sign, decimal point and exponent.

add tests to check these limits.



git-svn-id: http://skia.googlecode.com/svn/trunk@872 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/StringTest.cpp b/tests/StringTest.cpp
index 781fed8..270ccfd 100644
--- a/tests/StringTest.cpp
+++ b/tests/StringTest.cpp
@@ -73,10 +73,16 @@
         { SK_Scalar1,   "1" },
         { -SK_Scalar1,  "-1" },
         { SK_Scalar1/2, "0.5" },
+#ifdef SK_SCALAR_IS_FLOAT
+        { 3.4028234e38f,   "3.4028235e+38" },
+        { -3.4028234e38f, "-3.4028235e+38" },
+#endif
     };
     for (size_t i = 0; i < SK_ARRAY_COUNT(gRec); i++) {
         a.reset();
         a.appendScalar(gRec[i].fValue);
+        REPORTER_ASSERT(reporter, a.size() <= SkStrAppendScalar_MaxSize);
+//        SkDebugf(" received <%s> expected <%s>\n", a.c_str(), gRec[i].fString);
         REPORTER_ASSERT(reporter, a.equals(gRec[i].fString));
     }
 }