[clang] Fix typos in comments

clang/include/clang/AST/ASTImporterLookupTable.h

 // Example 1:
 //   template <class T>
 //   struct X {
 //     friend void foo(); // this is never found in the DC of the TU.
 //   };
 // Example 2:
 //   // The fwd decl to Foo is not found in the lookupPtr of the DC of the
 //   // translation unit decl.
-//   // Here we could find the node by doing a traverse throught the list of
+//   // Here we could find the node by doing a traverse throughout the list of
 //   // the Decls in the DC, but that would not scale.
 //   struct A { struct Foo *p; };
 // This is a severe problem because the importer decides if it has to create a
 // new Decl or not based on the lookup results.
 // To overcome these cases we need an importer specific lookup table which
 // holds every node and we are not interested in any C/C++ specific visibility
 // considerations. Simply, we must know if there is an existing Decl in a
 // given DC. Once we found it then we can handle any visibility related tasks.

clang/test/Sema/alloc-align-attr.c

 // argument type
 void *test_bad_param_type(void) __attribute((alloc_align(1.1))); // expected-error {{'alloc_align' attribute requires parameter 1 to be an integer constant}}
 
 // argument count
 void *test_no_fn_proto(int x, int y) __attribute__((alloc_align)); // expected-error {{'alloc_align' attribute takes one argument}}
 void *test_no_fn_proto(int x, int y) __attribute__((alloc_align())); // expected-error {{'alloc_align' attribute takes one argument}}
 void *test_no_fn_proto(int x, int y) __attribute__((alloc_align(32, 45, 37))); // expected-error {{'alloc_align' attribute takes one argument}}
 
-void *passthrought(int a) {
+void *passthrough(int a) {
   return test_ptr_alloc_align(a);
 }
 void *align16(void) {
   return test_ptr_alloc_align(16);
 }
 void *align15(void) {
   return test_ptr_alloc_align(15); // expected-warning {{requested alignment is not a power of 2}}
 }
 void *align1073741824(void) {
   return test_ptr_alloc_align(8589934592); // expected-warning {{requested alignment must be 4294967296 bytes or smaller; maximum alignment assumed}}
 }