Report that a JavaInputStreamAdaptor is at end.

This prevents a naive caller from continuing to attempt to read.

BUG:17419670
BUG:17873145
Change-Id: Idd462ff9055aea42e8c7d5d58ef177f9e667385b

core/jni/android/graphics/CreateJavaOutputStreamAdaptor.cpp

@@ -78,6 +78,8 @@ private:
                 env->ExceptionDescribe();
                 env->ExceptionClear();
                 SkDebugf("---- read threw an exception\n");
+                // Consider the stream to be at the end, since there was an error.
+                fIsAtEnd = true;
                 return 0;
             }
 
@@ -92,6 +94,9 @@ private:
                 env->ExceptionDescribe();
                 env->ExceptionClear();
                 SkDebugf("---- read:GetByteArrayRegion threw an exception\n");
+                // The error was not with the stream itself, but consider it to be at the
+                // end, since we do not have a way to recover.
+                fIsAtEnd = true;
                 return 0;
             }