Remove EXTENSION_FUNCTION_ERROR define.

This is currently unused, and has been so for quite some time.

Bug: None
Change-Id: If1504fcec2aee489ce6c53e686ef433d26d4849c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1723166Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Commit-Queue: Istiaque Ahmed <lazyboy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#681908}

extensions/browser/extension_function.h

@@ -75,13 +75,6 @@ class QuotaLimitHeuristic;
 #define EXTENSION_FUNCTION_PRERUN_VALIDATE(test) CHECK(test)
 #endif  // NDEBUG
 
-#define EXTENSION_FUNCTION_ERROR(error) \
-  do {                                  \
-    error_ = error;                     \
-    this->SetBadMessage();              \
-    return ValidationFailure(this);     \
-  } while (0)
-
 // Declares a callable extension function with the given |name|. You must also
 // supply a unique |histogramvalue| used for histograms of extension function
 // invocation (add new ones at the end of the enum in