[Fix] (MG_Impl/GLImpl): stop double-recording GL errors for a bad program handle

glBindFragDataLocation, glGetFragDataLocation and glGetFragDataIndex each
recorded a redundant GL_INVALID_OPERATION on top of the error that
TryToGetProgramObject already recorded (GL_INVALID_VALUE for an unknown
name, GL_INVALID_OPERATION for a non-program object). One bad call thus
queued two errors, so an app calling glGetError twice saw a spurious
second error, and any following code that expects a clean error queue
(e.g. a later test) picked up the stale one.

Drop the second RecordError from all three call sites and rely on the
single error TryToGetProgramObject already reports -- matching the clean
`if (!programObject) return;` pattern the rest of GL_Program.cpp uses. The
first, app-visible error is unchanged; only the redundant second is gone.

ProgramTest's invalid-handle case now asserts exactly one error (mutation-
verified: reintroducing the second record fails it) and keeps a defensive
error-queue drain. ProgramTest 24/24.

MobileGL/MG_Test/Program/ProgramTest.cpp

@@ -1564,8 +1564,10 @@ TEST_F(ProgramTest, GetFragDataIndexRejectsInvalidProgram) {
     // routes through the shared program-name check, which records GL_INVALID_VALUE for an unknown name.
     EXPECT_EQ(GetFragDataIndex(999999u, "fragColor"), -1);
     EXPECT_EQ(GetError(), GL_INVALID_VALUE);
-    // The name check and the entry point each queue an error for an unknown handle; drain the rest so
-    // no stale error leaks into a later test (the fixture does not reset the error queue).
+    // Exactly ONE error is recorded per bad call: the redundant second GL_INVALID_OPERATION that the
+    // FragData entry points used to queue on top of the name check has been removed.
+    EXPECT_EQ(GetError(), GL_NO_ERROR);
+    // Defensive drain: keep the shared error queue clean regardless (the fixture never resets it).
     while (GetError() != GL_NO_ERROR) {}
 }