Don't append newline to empty InfoLog stream.

src/libANGLE/InfoLog.h

@@ -39,7 +39,7 @@ class InfoLog : angle::NonCopyable
         ~StreamHelper()
         {
             // Write newline when destroyed on the stack
-            if (mStream)
+            if (mStream && !mStream->str().empty())
             {
                 (*mStream) << std::endl;
             }

src/libANGLE/Program.cpp

@@ -858,7 +858,10 @@ void InfoLog::appendSanitized(const char *message)
         }
     } while (found != std::string::npos);
 
-    *mLazyStream << message << std::endl;
+    if (!msg.empty())
+    {
+        *mLazyStream << message << std::endl;
+    }
 }
 
 void InfoLog::reset()

src/libANGLE/Program_unittest.cpp

@@ -26,6 +26,17 @@ TEST(InfoLogTest, LogLengthCountsTerminator)
     EXPECT_EQ(3u, infoLog.getLength());
 }
 
+// Tests that the log doesn't append newlines to an empty string
+TEST(InfoLogTest, InfoLogEmptyString)
+{
+    InfoLog infoLog;
+    EXPECT_EQ(0u, infoLog.getLength());
+    infoLog << "";
+
+    // "" = 3 characters
+    EXPECT_EQ(0u, infoLog.getLength());
+}
+
 // Tests that newlines get appended to the info log properly.
 TEST(InfoLogTest, AppendingNewline)
 {